The Red Sox have called Matt Barnes up in the past, but never with the long-term intention being for him to be a major piece of the bullpen. That's now changed, though, as Boston announced that they promoted Barnes to the majors on Saturday, and optioned Travis Shaw back to Triple-A Pawtucket in order to make space.
Shaw was only up for a one-day stint in order to keep Boston's bench intact on Friday for the series opener against the Blue Jays: with Hanley Ramirez sitting due to his injured shoulder and David Ortiz suspended for a day, the bench was lighter than usual. With Ortiz back, though, the Sox were able to call up Barnes to add him to the pen, and chances are good he'll be sticking there from here on out.
Barnes was drafted in 2011 with the 19th-overall selection, and has been a starting pitcher throughout his minor-league tenure. The Sox officially moved him to the bullpen earlier in the week, though, as that will be how he'll be used in Boston. Barnes might someday be a big-league starter, but with his somewhat inconsistent command and without three pitches he can always rely on, relief might be the best place for him in the long run, too.
With that being said, shifting to the pen might give him the experience attacking hitters that he needs to take those finals steps towards becoming a successful starter. It's no guarantee, but it likely gives him a better shot than trying to make it as a starter against Triple-A bats for another year would.