What he has become is fairly obvious. Will Middlebrooks is the prospect with the glimmering future, the player who at age 23 is in the process of unlocking his considerable potential, emerging as an elite prospect.

At a time when talent at third base appears to be down across the game, Middlebrooks stands out. He can not merely hit but crush the ball, and he is considered a terrific defensive talent. Moreover, he oozes confidence, as evidenced by a big league debut in which he could step to the plate, certain of his approach, and go 2-for-3 with a walk, a steal and most notably a double that he lined to right against a pitcher (Brandon McCarthy) who was in the process of shutting down virtually all of Middlebrooks' teammates.

Middlebrooks, in short, looked like a player who knew he belonged on Wednesday, and with good reason, coming off of his dominant performance in the season’s first four weeks in Triple-A.

'Twas not always thus.

While Middlebrooks solidified his status as the top Red Sox prospect with a highly favorable first impression in his debut, the previous time he played in Fenway Park came under considerably different circumstances. In 2008, in his first professional season after getting taken in the fifth round of the 2007 draft and signing a $925,000 bonus to pass on college, Middlebrooks arrived in Fenway Park amidst a career start that made his future look anything but certain.

Middlebrooks was playing for the Lowell Spinners of the New York-Penn League at the time, and for much of the first seven-plus weeks of the season, he appeared hopelessly overmatched. The distance that he traveled in less than four years to return to Fenway Park on Wednesday night is little short of staggering.

Gary DiSarcina, Middlebrooks' manager that year in Lowell, recently sat in a minor league dugout with Mike Trout in his current capacity as the Angels minor league field coordinator. Trout -- a dazzling five-tool talent who was called up at the end of April by the Angels -- and Middlebrooks became close while Arizona Fall League teammates last fall.

As DiSarcina and Trout sat together on a night off for the prospect, the conversation turned to Middlebrooks.

“I told him, ‘Mike, if you had seen this guy four years ago when I had him in Lowell, you would just be in total shock. He was a high school kid playing in a college league and he was just overmatched for the first six weeks,’ ” DiSarcina said.

It is fascinating to recall Middlebrooks at that uncertain time in his career. To recall the depths of his struggles -- not just in 2008 with Lowell but also the subsequent year in Greenville -- helps to explain the developmental process that led the 23-year-old to his current position as a player whose promise at the start of his big league career seems virtually boundless.

A HEAD-SPINNING START IN LOWELL

He was homesick. At a time in his life when Middlebrooks would have been a freshman at Texas A&M, a bit less than 300 miles from his native Texarkana in 2008, Lowell, Mass., felt like the far end of the world.

In high school, Middlebrooks had been the charismatic multisport star, the quarterback who led his team to the state championship and had for much of his life harbored visions of an NFL future. But in his late high school career, his baseball talents began to overtake the visions of gridiron glory he shared with close friend (and current Patriots backup quarterback) Ryan Mallett. 

On the mound, Middlebrooks would wing a fastball in the mid-90s. As a shortstop who fancied himself in the mold of a Cal Ripken, he could step to the plate for a workout at The Ballpark in Arlington and mash one ball after another into the left field seats in batting practice. He could do no wrong.

“Where he came from, he was a big fish in a little pond,” recalled DiSarcina.

Most professional players fit that bill in high school. That being the case, as the reality of a more level playing field sets in, it’s not uncommon for first-year players, especially those who sign out of high school, to feel adrift at the start of their professional careers, and certainly Middlebrooks was aptly described in that fashion.

Players who struggle question whether they made the right decision in choosing pro ball over college. Particularly given that Middlebrooks walked away from a two-sport offer to play football and baseball at Texas A&M, those feelings were undoubtedly intensified as the reality of his challenge in pro ball became clear.

“I was very raw coming out of high school -- very raw. I was basically an athlete, not a baseball player,” Middlebrooks reflected. “I played sports year-round. Whatever season it was, I was doing it. I never focused on one sport for a long period of time in high school.”

Middlebrooks cannot say, with the benefit of hindsight, whether that multisport background left him behind other players at the start of his pro career. What he does know is what transpired on the field.

In terms of performance, he was awful. While the Red Sox typically keep premium position prospects at shortstop as long as possible, with Middlebrooks they decided to embrace the inevitable transition (based on body type) to third base on the day that he showed up in Lowell following the months spent in Fort Myers in extended spring training. So, defensively, he had to make the adjustment to a new position, with the corresponding uncertainty that came with the move.

Offensively, he was a high school kid in a league where the majority of pitchers are recent draftees out of college, and he seemed ill-positioned for success. More than a month into the year, he was hitting .187 with a .227 OBP, .231 slugging mark and .458 OPS. He was near the bottom of the league in virtually every offensive category save for strikeouts, where he was near the top of the leaderboard.

“I was getting off to a slow start,” Middlebrooks said. “I hated it.”

It showed. DiSarcina saw a player who was constantly on the phone with his support network at home. At that point, he was still lanky, with his physical maturation still in front of him, but the more glaring concerns related to his state of mind.

“His issues were a lot on the mental side, not competing. He had a lot of days where he’d just take fastballs middle-away and not swing at them,” DiSarcina said. “He had no idea what he looked like, he had no idea how poor his body language was. He had no idea how insecure he looked.”

Middlebrooks worked and he cared, but he could not apply his work to achieve improved results in the early stages of that year in Lowell. Spinners hitting coach Luis Lopez, DiSarcina recalled, was “beating himself up, beating his head against a wall,” because the considerable time that he spent with the prospect offered no evidence of progress in games.

Day after day, Lopez would talk with the 19-year-old before the game about his approach. Day after day, Middlebrooks would step to the plate in a game as if those conversations never happened.

“I know there were some days when he’d be happy just to hit the ball -- first half of that season, if he just put the bat on the ball, he was happy. You could see it,” DiSarcina said. “That’s a sign of being insecure and not confident. He did not have a plan. He was incapable of taking all the work he did with Luis into a game because he mentally wasn’t there.”

The Red Sox had expected there to be a transitional struggle to professional ball, and the organization tried to offer a support system. Jim Robinson, the Texas-area scout who signed Middlebrooks, was in regular touch, as was scouting director Jason McLeod. But ultimately, it was DiSarcina who recognized that the time for hand-holding had passed.

Five or six weeks into the season, DiSarcina had seen the frustration in both Middebrooks and Lopez. He had become aware, through conversations with team officials on both the player development and scouting side, of Middlebrooks’ competitive pedigree, of the fact that he had relished responding to challenges while a championship-caliber athlete in high school.

“I brought him into the office about five, six weeks into the season and just challenged him to go out there and compete, walk up to the plate like that’s your batter's box and you’re going to do damage,” DiSarcina said.

The conversation was only 10 or 15 minutes. Middlebrooks was in sweatpants -- “He was dressed like a high school kid,” DiSarcina said -- and initially the player seemed almost sheepish.

“He wasn’t making eye contact with me,” DiSarcina said. “I said, ‘Will, when I’m talking with you, look at me in the eyes. Don’t look around the room.’ That’s part of the insecurity I was talking about, the young kid in him.

“He was walking up to the plate beaten. He was in the on-deck circle down 0-2, and his at-bat was already over. That’s kind of where his mentality was. I basically challenged him to compete. I said, ‘You’re not competing right now. You’re an out. You’re going up there and you’re an out, and I’m sick of it. If that’s how you’re going to be the whole year, you can sit on the bench.’

“He looked up at me, he gave a half-smirk and half-smile and said, ‘That’s what I look like?’ I said, ‘Will, you look like the last place you want to be is in the batter’s box, and not just for one at-bat but for four at-bats a night. You’ve got to challenge yourself and you’ve got to start competing because you’re just as good as anyone in this league.’

“He kind of looked at me again and said, ‘I didn’t know. I didn’t know. I didn’t know.’ He said it three or four times, ‘I’m sorry, I didn’t know.’ I said, ‘Hey, don’t apologize -- go up there and compete.’ ”

For Middlebrooks, it was a career-changing conversation. He needed a different voice in order to snap to attention and be ready to take ownership of his career.

“He didn’t scream at me, but he got his point across that you’re so much better than you think you are and how you’re playing, so pull your head out of your butt and play how you’re capable of playing,” Middlebrooks recalled. “That was really what turned everything around for me. It was just as simple as someone saying, ‘You’re better than what you’ve been. Let’s go.’ ”

THE FUTURES AT FENWAY: A HARBINGER

On Aug. 9 that year, Lowell participated in the Futures at Fenway game, and Middlebrooks had his opportunity to glimpse where his career might go. Still, even though he’d made positive strides following his sit-down with his manager, he carried a .225/.263/.317/.580 line with him to Boston.

That day was different. Middlebrooks put on a show in batting practice, smashing pitches over the Monster seats. His swing remained authoritative during the game. In a 12-inning game, Middlebrooks went 3-for-6 with a double while driving in three, including a walkoff single up the middle in the 12th.

In the last hit, he showed the ability to compete that had been lacking earlier that year. He swung and missed at a slider out of the zone early in the count, checked his swing and let a similar pitch pass for a ball on a two-strike count and then, when the pitcher came back with a fastball away, he lined it up the middle for a walkoff that resulted in his being mobbed by his teammates in a ballpark that has had so many similar moments.

On Wednesday, prior to playing at Fenway for the first time since that day in 2008, Middlebrooks remembered only the hazy outline of that game. But he understood its significance.

“That really did turn around my season,” he said. “Any time you’re struggling and you can see a glimpse of getting out of that hole, it’s huge. That’s what gets you out of it and builds your confidence to let you know you can do it.”

From that day forward in Lowell, Middlebrooks not only carried himself like a prospect, he performed like one. He hit .313 with a .370 OBP, .478 slugging mark and .847 OPS.

“When I go back to that hit in Fenway Park, for me, that was a turning point in Will’s minor league career,” DiSarcina said. “With Will, having that day, his chest was out, his head was held high and I remember saying to myself, ‘He’s got it. He doesn’t need to have those conversations any more. He’s going to compete.’ That’s kind of where I pinpoint his career turning around.”

SELF-ASSURANCE IN THE FACE OF MORE ADVERSITY

Middlebrooks finished his first pro year with numbers that were respectable, though hardly eye-popping. Still, given where his season had been, the fact that he finished the year with a .254 average, .298 OBP, .368 slugging mark and .666 OPS created considerable optimism that his future was on the right path.

That impression was further solidified by the work Middlebrooks put in during the offseason. He was strong but lean in his first pro season. That offseason, he filled out.

“I had played with [four-time All-Star third baseman] Troy Glaus, and his body starting to resemble him a little bit just the way it was growing,” DiSarcina said. “When I saw him in spring training and in Greenville, he was starting to looking like a man.”

For his age 20 year, Middlebrooks was sent to Single-A Greenville. In some respects, that season -- when he was in some respects overlooked as a prospect while playing with others who had more impressive years, such as Casey Kelly, Anthony Rizzo, Tim Federowicz and Ryan Lavarnway -- offered even more significant evidence of the direction of his career.

“The biggest year, to me, by far, was the Greenville year,” said assistant general manager Mike Hazen, the Red Sox farm director for most of Middlebrooks’ advance through the system. “By far.”

Middlebrooks once again got off to a brutal start. The numbers made the opening of his time in Lowell look like a hot streak by comparison.

Through the first game of a doubleheader on May 18, Middlebrooks was hitting .133 with a .212 OBP, .183 slugging mark and .395 OPS. He had struck out in nearly half (26 of 60) of his at-bats. Across the board, his numbers were among the bottom handful or so of players in the league.

But the player was different. Despite his struggles, he remained self-assured.

“He struggled that first half season in Greenville, but he’d be like, ‘Hey man. I’m all right. I’m good. I promise, I’m good,’ ” Hazen remembered. “He said, ‘I’m fine. I promise, I’m good.’ ”

For their part, the Sox would offer assurances that no matter what the numbers said, he would continue to play every day, and that the team believed in the talent. Soon, his play would support that confidence. Over his last 85 games of that year, Middlebrooks hit .288 with a .374 OBP, .446 slugging mark and .819 OPS.

DiSarcina -- who was in Greenville in the early part of that season to work with Middlebrooks on his defense at third -- suggested that the player’s early struggles merely reflected an adjustment to his physical growth, adapting to what his newfound strength and 15-20 pounds of extra muscle could allow him to do, finding comfort in the idea that he could drive the ball to all fields.

He looked at Middlebrooks and saw a player who looked and acted like a big league third baseman. The sound of the ball off his bat reminded DiSarcina of Glaus, and Glaus and Scott Rolen came to mind for DiSarcina in terms of how Middlebrooks simply looked the part of someone who should man the hot corner.

The apex of his year came in the playoffs. In the first round of the series between Greenville and the Asheville Tourists, the Drive trailed, 2-1, entering the ninth inning, and Tourists right-hander Adam Jorgenson -- amidst a dominant year in which he saved 27 games, having converted every opportunity since April 28, and struck out almost 12 batters per nine innings -- was on the mound to close it out.

Lavarnway tied the game with a solo homer, and Middlebrooks followed by belting a solo homer that proved the game-winner. Hazen was there, and for him that moment was even more significant than the Futures at Fenway.

“That, to me, was sort of the defining moment for the guy because it was the first time that he hadn’t just held his own but that he excelled in the pressure situation, the tight moment, the key spot. He stepped up and did it,” Hazen said. “Again, he learned through that whole season that this is a long season. Things happen. You need to be able to battle through them to even out those dips.”

AND NOW …

In 2008 and 2009, Middlebrooks was talented but raw, prone to slumping for a month at a time. It was in those formative years in Lowell and Greenville where he figured out what it meant to be a professional, what it took to respond to adversity in order to hold one’s own on the diamond.

Whereas he endured dreadfully slow starts in those two years, he hit the ground running in High-A Salem in 2010, and it was there that his prospect stock took off. He was one of the dominant players in the Carolina League that year, particularly early, getting named to an All-Star team for the first time as a pro. He hit .276/.331/.439/.770 that year, wrapping up the year with a dozen homers, including a half-dozen during one brief stretch in August that, for the first time, offered evidence that he could translate his raw power to home runs.

Middlebrooks carried that performance into a breakout 2011 campaign in which he dominated in Portland. He was named the top hitting prospect in the Eastern League by Baseball America after hitting .302/.345/.520/.865 with 18 homers in just 96 games, leading the league in RBI with 80 at the time of his August promotion to Pawtucket.

Yet even with that performance -- which came with recognition as the top prospect in the Red Sox system -- no one could have reasonably expected the blast out of a cannon that has been Middlebrooks in 2012. His nine homers in 24 games for Pawtucket were more than he hit in 2008 and 2009 combined in Greenville, nearly as many as the 12 he hit in Salem.

Yet it is not just where the all-fields blasts are going but also the process that is leading to them that has been eye-opening.

“This guy is crushing two-strike breaking balls from right-handers. He’s hit two home runs on 3-0 pitches, things that make you believe that this guy is figuring some stuff out,” Hazen said. “You’re seeing the maturation of a hitter.”

It is the translation of potential to results by a player who took ownership of his career in spectacular fashion. Middlebrooks has dedicated himself to becoming an elite baseball player, having paid his own way to Athletes’ Performance in the past two offseasons, and he is a far cry from the player who appeared lost in his first professional season in 2008.

DiSarcina saw Middlebrooks play in the Arizona Fall League last year, and while sitting next to Angels amateur scouting director Rick Wilson, he was amazed by the player he saw.

“I was talking with [Wilson] about how far he’s come, just how he looks. He just looks like a big leaguer,” DiSarcina said. “He walked up to the plate like a big leaguer, he got in the box like a big leaguer. As the words went out of my mouth, he hit a line drive off the left-field fence for a double. Running the bases, he looked like a big leaguer. I hadn’t seen him play in two years. But talking to him, it’s the confidence side of things. He’s grown up to be a man. That’s where I see him now.

“I had him as a baby. He was a piece of clay that could be molded. If he wanted to tell me to [shove] off, he could have told me to [shove] off, but he didn't,” he added. “The last thing I really pounded on him [in Lowell] was to be a leader. 'I want you to be a leader. Be the first one out here for the drills, take your ground balls, pat your teammates on the back. Be a leader, see the big picture.' That's how I perceive Will when I look at him: middle-of-the-order guy who is going to be a leader.

“He was a baby when I had him, and I'm proud as heck of him. He grew up to be a man.”