The Red Sox have added a reliever to the mix for 2013, claiming Sandy Rosario off of waivers from the Miami Marlins. This occurred after Scott Cousins was claimed by the Marlins from the Blue Jays, and was initially reported by the Miami Herald's Clark Spencer.
Rosario spent most of the 2012 season in Miami's minor-league system, pitching 31 innings at three levels while striking out nearly six times as many batters as he walked. He was 26, though, and has had far less success in limited time in the majors. He entered 2012 as the Marlins 29th-ranked prospect according to Baseball America:
Rosario led minor league relievers with 125 strikeouts in 92 innings in 2010, spending most of the season in low Class A but finishing it in Florida. He again got a taste of the big leagues last fall, though his stat line wasn't nearly as gaudy as his previous campaign. Rosario fills the zone with 92-95 mph fastballs, reaching 97 at times, but his four-seamer is fairly straight. When he doesn't locate his heater where he wants to, it gets hit. He's working on a two-seamer that should have more life. Rosario's low-80s slider gives him a potentially solid No. 2 pitch, but he lacks a true offspeed offering to disrupt hitters' timing. Scouts have expressed concern with his long arm action, which interferes with his command and gives hitters a good look at his pitches. A closer in 2011, he profiles more as a seventh-inning arm in the majors. Rosario will contend for a big league job this spring but may need more time in Triple-A.
The Red Sox have attempted to straighten out arms with issues like this before, so Rosario becomes yet another project reliever that either pitches his way onto the roster in the spring, or one optioned to Pawtucket to continue to work on evolving his repertoire.
The reason Rosario didn't pitch much overall this past season was due to a quad strain that caused him to miss 67 games. His injury history is nearly empty besides that, though: his troubles have had more to do with that too-straight four-seamer.
He's not an exciting acquisition, but Boston has done well with this type of piece recently. Throw him in the 40-man pile, assuming he even lasts long enough for the Red Sox to hold on to him, and see which reliever projects survive the winter. Their roster is quite crowded, after all.
Crowded enough that outfielder Che-Hsuan Lin was removed from the 40-man in order to make room for Rosario. Lin was designated for assignment, so now he is eligible to be claimed on waivers by the other 29 teams. It's no guarantee that the outfielder, who can field excellently but hit just .247/.323/.316 for Triple-A Pawtucket, will end up anywhere else. Either way, he's no longer on Boston's crowded 40.
Lin has been with the Red Sox since 2007, when he was signed as an international free agent out of Taiwan. He's never been much offensively, but can draw a walk, and between his arm and range, could have a career as a bench outfielder in the majors. Sox Prospects currently rates Lin as the #44 prospect in the organization.