BALTIMORE — And so it would appear that the Red Sox are deep into the Carlos Beltran sweepstakes. Again.

According to a FoxSports.com report, the Red Sox are among the most aggressive teams pursuing the Mets outfielder, who is enjoying a career renaissance at age 34. After missing much of the last two seasons with a variety of ailments, Beltran has re-established his All-Star credentials this year. He is hitting .293 with a .389 OBP, .523 slugging mark and .911 OPS, along with 14 homers and an NL-leading 30 doubles.

Despite that performance, the Mets — who are 48-48, 12 games behind the Phillies in the NL East and 8½ lengths behind the Braves in the wild card race — are willing to move the free agent-to-be. And the Sox, who have endured poor right field production this year (chiefly due to the struggles of J.D. Drew, who is hitting .223 with a .630 OPS), appear to be one of the teams interested in Beltran.

That fact should come as little surprise. The Sox, according to a team source, have made a number of runs at the outfielder through the years. But none is more fascinating to contemplate than the Sox’ push to land him in 2004.

That year, Beltran was coming into his own as one of the game’s true five-tool talents for the Royals. Kansas City entered the season with high hopes, having gone 83-79 the previous year, but the Royals got off to a brutal 8-20 start and were soon in the position of having to contemplate a trade for a budding superstar whom they had no hope of retaining when he became a free agent after the 2004 campaign.

And so, by early June, the Royals had made it known that they were listening to offers on Beltran. It was an uneasy reality for the 27-year-old, who had spent his entire career with the club that had selected him out of Puerto Rico in the second round of the 1995 draft.

“At the beginning, it was a little bit uncomfortable, because every day I thought maybe today might be the day that I’m traded. But one day I had a conversation with Allard Baird, the general manager,” Beltran recalled at the All-Star Game last week, citing the former Royals GM who is now a top Red Sox executive. “He told me, ‘Don’t listen to rumors. If you don’t hear from me, nothing’s going to happen.’ That really took some weight off me, off my shoulders. I didn’t worry anymore about being traded. … That was good for me until that day came that I was going to be traded to Houston.”

Beltran had a close relationship with Baird, who had climbed the ranks of the Royals front office while Beltran was moving through the Kansas City system. Indeed, the two remain close to this day, exchanging occasional text messages.

“We kind of came up together to the big leagues,” he recalled. “We kind of developed that relationship and were there for each other.”

And so, given reassurance by Baird, Beltran was happy to focus on playing the game at an exceptional level. He tuned out the rumor mill, and said that he was unaware of the teams vying for his services.

That, no doubt, spared him plenty of confusion, since the suitors for Beltran’s services were numerous. He was coming off a 2003 season in which he hit .307 with a .389 OBP, .522 slugging mark, .911 OPS, 26 homers, 100 RBI and 41 steals in 45 attempts while playing Gold Glove-caliber defense in center.

The Sox were among the teams that coveted him. With Trot Nixon out for the first two-plus months of the 2004 season due to a bulging disc in his back, the Sox recognized the possibility of upgrading their outfield in a fashion that would impact them both offensively and defensively.

The Royals wanted a third baseman and catcher who were either close or ready for the big leagues. The Sox were among the teams that had the prospects to match up, as they featured 24-year-old catcher Kelly Shoppach (then a player who hit for low average but who had plenty of power and who walked quite a bit in Triple-A Pawtucket) and 25-year-old third baseman Kevin Youkilis.

Youkilis had emerged as an intriguing prospect due to his tremendous plate discipline, someone who put up huge walks totals and hit for a respectable average. He held his own in his first big league callup that year, filling in capably for Bill Mueller.

At the time, however, Youkilis lacked apparent athleticism and did not feature the jaw-dropping tools of elite prospects. He had shown little power to that point in his minor league career, and so even as the Royals felt that he would be a productive major league hitter, they felt that his ceiling might be limited.

While the Royals considered the Sox’ offer seriously, Kansas City ultimately decided to pursue a three-way deal with the Astros and Athletics that netted the Royals third baseman Mark Teahan and catcher John Buck as well as right-hander Micah Wood. Closer Octavio Dotel ended up going from Houston to Oakland in the deal.

“I didn’t know the teams that Allard talked to, but all he told me was that he was in conversations with the Houston Astros. He said he was going to call me in two hours, and that things like this could fall off,” Beltran said. “In two hours, [Baird] called and said, ‘Carlos, you got traded to the Houston Astros.’ He didn’t need to do what he did. But he just handled it so professionally with me, that I said, ‘I will always appreciate it.’ ”

And so it was that Beltran parted amicably with the Royals and landed with the Astros, and not the Sox, in pursuit of a championship in 2004. The dislocation could have been jarring, but his exit from Kansas City (for whom he hit .278 with a .367 OBP, .534 slugging mark, .901 OPS, 15 homers and 14 steals) was eased by Baird. Meanwhile, his entry into Houston (for whom he would hit .258/.368/.559/.926 with 23 homers and 28 steals in 90 games) proved smoother than expected.

“I was trying to be part of something. They had [Jeff] Kent, they had [Jeff] Bagwell, they had [Craig] Biggio, they had [Lance] Berkman, they had so many ballplayers,” Beltran recalled. “When I got there, I just wanted to do my part. I ended up having a good second half with them, but they made me feel like part of it, like I was with them since spring training. I just went out to have fun. Unbelievable things happened for me and the organization.”

Indeed.

The Astros, who were two games back in the wild card hunt on the day of the Beltran deal, ended up zooming into the postseason. And it was there that Beltran performed like a superhero, nearly carrying the Astros into the World Series against the Sox.

Beltran hit .435 with a .536 OBP, 1.557 OPS, eight homers, 14 RBI and six steals in 12 playoff games that year. The Astros ended up dropping Game 7 to the Cardinals, 5-2, but the opportunity to experience the postseason and to emerge as a difference-maker under the spotlight proved thrilling for the outfielder.

“I just told myself, I’m going to go out, have fun and enjoy myself because as a ballplayer, when is my next opportunity going to be?” Beltran said. “I had no expectations. It was my first playoffs. I just went out and got in position where I was feeling good at the plate. It’s just one of those stretches where you get hot.”

It was a deal that worked out brilliantly for the Astros, of course, but that also ended up proving fortuitous for the Sox, who not only won the 2004 World Series but retained a future star in Youkilis. As a first baseman, he played a key role in the 2007 title run and has served as a lineup anchor for the last six years.

Now, seven years later, Beltran — who is nearing the end of his seven-year, $119 million deal with the Mets — finds himself once again on the cusp of free agency, and consequently, once again amidst a tug of war by teams with October ambitions. He has been connected to the Sox, Phillies, Giants, Pirates and numerous others who see the potential to acquire a difference-making switch-hitter.

At the All-Star Game, Beltran made clear that he wants to win with the Mets, but he also said that he would be willing to waive his no-trade clause to move to a contender. He explicitly cited the Red Sox as one team to whom he would accept a trade.

“They’re in first place,” Beltran said. “That’s a no-brainer.”

Beltran has twice been to Game 7 of the NLCS, and twice come up just short — both times to the Cardinals. His last playoff memory, in fact, is of having taken an Adam Wainwright curve for a called third strike with the bases loaded and two outs in the bottom of the ninth inning of a 3-1 Game 7 defeat.

Now 34, Beltran is motivated to return to that October platform.

“Winning is everything,” Beltran said. “As a ballplayer, you work hard in the offseason, spring training, in the season to try to get to that level where you’re playing meaningful games. You’re playing in games where, man, the atmosphere is unbelievable, the adrenaline is high, the concentration is twice as good as the season.

“As a ballplayer, you want to be in those situations. Those are the situations where you prove yourself. Whatever happens, happens, but you have that experience that a lot of players don’t have.”

Will Beltran now have the chance to experience those highs with a team that nearly landed him seven years ago for a similar purpose? Stay tuned.