There are players whose dazzling athleticism commands the attention of scouts in a way that ensures their draft prominence. Mike Napoli is not among them.

Instead, he is a case study in the need to look beyond first impressions, to watch a player over time and move past superficial impressions to appreciate his skill set.

That is the exercise that had the Red Sox circling Napoli -- whose signing to a three-year, $39 million deal is expected to be announced in a press conference sometime this week, perhaps as early as today -- as the team’s foremost free agent target of the offseason, the 2012 batting average of .227 and discussions of defensive limitations be damned. In some respects, the Sox repeated a process that led to Napoli’s entry into professional baseball more than a decade ago, one in which a current member of the team’s baseball operations staff played a critical role. 

In 2000, Todd Claus -- now a Sox international scouting cross-checker -- was a Florida area scout for the Angels. In that capacity, he came across an 18-year-old at Charles Flanagan High School in Pembroke, Fla., who didn’t necessarily fit the prospect prototype.

“His body kind of looks the same as it does now. Actually, he’s probably in better shape now than he was then. He was kind of a mature guy. He had a full beard in high school. He had a scholarship to LSU, and first time I laid eyes on him, I was like, ‘Okay, not exactly how you script it,’ ” Claus recalled by phone. “He was hitting leadoff for his high school team so they wouldn’t intentionally walk him. He thought he was a speed demon -- he probably had 20 stolen bases or something. They’d walk him or he’d get a hit and steal second, steal third.

“He was a good baseball player in high school. But lots of people, I think, couldn’t get past his body,” continued Claus. “I remember taking Donny Rowland in there, [the Angels] scouting director at the time. He was like, ‘This is your guy, huh?’ I was like, ‘That’s him.’ ”

Still, while the swing and physique were atypical for a prospect, Claus also couldn’t help but be impressed by the tremendous bat speed and power that the 18-year-old generated.

“He could always hit. This guy could mash, man. He hit the ball over the fence, and his strength was to right-center field,” Claus noted of Napoli’s ability to drive the ball out to the opposite field. “It was hard to get excited about him unless you saw him play a lot. He just didn’t fit -- his tools, he didn’t run great, he didn’t throw great and he was just kind of an okay catcher.

“But he squared up the baseball. He always hit the baseball. I got to see it over and over and over. The more I went to see him, every time I wrote a report on him, the report got better. I think it was because I wanted him so bad.

“I really liked his makeup as well. He’s a dirt bag. I mean that in the kindest of ways. He’s a baseball rat, loves the game and I loved his makeup and the way he got after the game, the way he competed in the batter’s box. He’s pretty much done that his whole career.”

Initially, Claus was somewhat conservative in his assessment of the catcher. On the 20-80 scouting scale, he tagged the slugging teenager with a 48, suggesting a potential big leaguer, but a role player rather than necessarily a starter.

But as he kept watching Napoli as a senior, the assessment kept rising. He nudged up to a 50, a potential big league starter but with defensive limitations. But he kept reconsidering and reconsidering, finally identifying him as a 55 -- a potential everyday player on a good team.

“That was pretty bold,” Claus acknowledged. “I just thought he was going to hit. I liked the makeup.”

The talent, Claus felt, suggested a player worth a pick in the first five or eight rounds. But Napoli -- who had a scholarship commitment to LSU -- remained on the board beyond that stage of the draft due to signability concerns. It wasn’t until the 17^th round of the 2000 draft (one of the most improbably impactful rounds in draft history, as Josh Willingham and Rich Harden also were taken in that round) that the Angels tabbed Claus’ guy.

While Napoli had an attractive scholarship offer, the Angels offered an above-slot bonus and a compelling recruiting pitch. At one point, when the team was in Tampa Bay to play the Rays, Napoli met the team and manager Mike Scioscia, took batting practice on the field and received a glove from Bengie Molina. He signed the next day.

A couple seasons later, Claus and Napoli intersected again, this time with Single-A Cedar Rapids of the Midwest League. It was Napoli’s first full season on a stacked team that featured 12 future big leaguers, including Ervin Santana, Joe Saunders and, perhaps most notably, catcher Jeff Mathis.

Napoli and Mathis split playing time behind the plate and DH (with Napoli also getting time at both first and third base), giving both a chance to develop their catching skills while also getting regular at-bats. Claus recalled the pitchers enjoying the opportunity to work with Napoli, who had a catcher’s acumen and an ability to control the running game.

“He never had a cannon, but he was very efficient with his footwork, his clean arm stroke and his accuracy,” said Claus. “He just made it all work. He just had the grinder mentality. He was a leader. Obviously, I had seen him do it in high school. He continued that into professional baseball.”

Still, from a pure tools standpoint, the 20-year-old Napoli didn’t necessarily stand out in comparison to the 19-year-old Mathis. The younger Mathis had bigger defensive tools and hit .287/.346/.444/.790 with 10 homers; Napoli hit .251/.362/.392/.754 with 10 homers.

Claus acknowledges that, when he was with Napoli in the minors, he didn’t necessarily see the ultimate shape that his career would take. As a 20-year-old, he had more development ahead of him on both the offensive side -- particularly given that shoulder injuries (including to his labrum) -- slowed his progress. Relative to the other elite catching prospects in the league, Napoli didn’t necessarily separate himself.

“When you get too close to it sometimes on the development side, you lose sight of the development picture with the crystal ball So, to say that I thought he was going to be a catcher in the big leagues for the next 15 years or 10 years, I can’t say that he stood out,” said Claus.  “Joe Mauer was in the league that year. He stuck out. You can say, Joe Mauer, that’s the guy. He was an easy one. Mathis, tools-wise, he was there with anyone. He could throw, had some pop, but he ended up being the backup.

“I didn’t know [Napoli] was going to be as high a quality of a hitter as he is. But he ended up being the guy,” he continued. “It took a little bit of time for his at-bats. … He had some battles. He had a tough road where he really had to grind out what he did in the minor leagues. Once he finally got healthy again, this was after I let him go, he was past me, he started hitting and I think his bat carried him to the big leagues.”

Now, Napoli’s bat has carried him through a formidable career as an under-the-radar masher. It took him four years from the time Claus had him in Cedar Rapids to reach the majors, but after that “tough road,” he’s now established himself. His .863 OPS since 2000 puts him in standout company, just behind Kevin Youkilis (.873) and Troy Tulowitzki (.868) and Robinson Cano (.864), and just ahead of Jose Bautista (.861) and Justin Morneau (.859).

Just as was the case as an amateur, Napoli’s track record and talents are oft-overlooked. Yet there is little doubt that he’s been an impact hitter and player for some time.

Claus has yet to get in touch with Napoli since he agreed with the Sox on his deal, but he’s excited about the inevitability that he will do so, that the two will cross paths again more than a decade after Claus first looked at a stocky amateur and saw a future big leaguer.

The scout will be the first to admit that he didn’t foresee the precise path that Napoli’s career has since taken. Nonetheless, while taking a moment to backtrack a dozen years and recall the process whereby he helped Napoli get his professional start, Claus also sees plenty about which to be excited with the player’s future.

“I’m just happy to have him in this organization because of the clubhouse presence and the middle-of-the-order lineup presence that he’ll bring to our club. I’m happy he’s here,” said Claus. “I’m excited for him and his family. He certainly deserves it, and so do we -- the Red Sox deserve a player like him. He’s going to give it his all.”