It is a place that will always have meaning for Masterson, since it is where he made his Major League debut, and because it was his first baseball home.
Masterson, whose Cleveland Indians are at Fenway for the final four games of the regular season, was the centerpiece of the deal that brought Victor Martinez's high-impact bat to Boston.
"It's great to see that the player they traded for, it worked out," Masterson said. "Otherwise it would be like, 'Man, they should have just kept me.' But no, it's been great. For me, it's been a transition. It's nice to see Victor come over and do a great job, because he was so well-loved. It was almost more bittersweet for him because he had been with Cleveland even longer, but when he has the excitement of coming to the contender, it looks like he's come in and made his presence known."
The timing of the 24-year-old Masterson's return to Boston certainly created some mixed emotions. The Red Sox, after all, are getting ready to embark on the postseason, which Masterson played a central role in. The Indians are finishing out a rebuilding season.
"It's different. It's kind of weird," Masterson said. "You think about that, when the transition was made. You go from a team that was fighting for the playoffs and has now made it, to the team that's hoping for next year, and maybe years to come, to be in the playoffs. It's a great opportunity, but for the short term, you're like, 'Oh man.'"
Last year, in the American League Division Series, Red Sox manager Terry Francona brought Masterson on in the eighth inning of a do-or-die situation against the Angels and he came through. He was Jonathan Papelbon's main setup man through the end of that postseason.
"It was so cool last year to pitch in just about every playoff game and warm up for every game, and of course I was facing the same guys -- Torii Hunter and Vladimir Guerrero," said Masterson. "But yeah, it was kind of a good memory and it makes me hope [the Indians] can get back there again.
"We have the youngest roster in the Major Leagues in Cleveland. We definitely have a lot of good players with good potential. We just have to put it together. We have some pieces and I think we'll get a few more, and hopefully, we can maybe be playing Boston in the playoffs next year."
Since coming to the Indians, Masterson has been used exclusively as a starter. Originally, he would have ended his 2009 season on Sunday against the Red Sox. But that changed, thanks to the Indians getting rained out on Tuesday, which pushed Masterson's last start to Wednesday. The outing wound up being a complete-game gem against the White Sox, with Masterson striking out 12 and allowing one run.
"It's been a long year," Masterson said. "It's been weird because I relieved, made the transition to starting, back to relieving, transition to starting again and then getting to know new teammates and getting to know what they're all about, a new city. It's been long, but it's been fun -- some nice learning experiences on the mound as we've been starting, but it's been exciting. It was really cool to be able to end it where everything was able to come together, where it was supposed to be. That's kind of what took place yesterday."
And even if the trade worked out for the Red Sox, they've lost no appreciation for the type of pitcher and person Masterson was during his time in Boston.
"He's one of everybody's favorites here," said Red Sox manager Terry Francona. "How could he not be? He pitched well. I heard he threw the ball well. You're not going to get guys like Victor without giving up something good."
Ian Browne is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.