Rubby De La Rosa
De La Rosa's last chance to stick as a starting pitcher was possibly something of an accident: prospect Matt Barnes was limited in spring training and hasn't pitched for the PawSox yet in 2014 at the same time knuckler Steven Wright was on the 60-day disabled list, leaving one of the five rotation spots open for De La Rosa, a pitcher the Red Sox seemed to be transitioning to relief after a disappointing 2013. De La Rosa has made the most of it to this point, at least, striking out 14 batters in 16-2/3 innings against just three walks.
There are still concerns with the electric righty. Durability and fatigue have been issues in the past, with De La Rosa unable to successfully ratchet his innings back up last year, in what should have been his first fully healthy season since undergoing Tommy John surgery towards the end of 2011. He's already 25 years old, and only has one option year remaining after this one, so figuring out what his role will be is something that needs to happen soon in order to properly prepare him for it. If he can keep his velocity and mechanics deep into starts now even further removed from Tommy John surgery, the Sox should probably keep him in the rotation even when Barnes and Wright return -- Wright could be valuable, but against De La Rosa's upside, he's a curiosity who happens to be versatile and already on the 40. If that isn't the case, though, and De La Rosa is laboring to make it to six innings against Triple-A hitters he should be outright dominating at this stage in his career, then the bullpen awaits.
Now, if De La Rosa is still dealing at the same time Henry Owens is finished with his education at Double-A, then who knows what the right answer is. That's a good problem to have, though.
Bryce Brentz, RF
Brentz was added to the 40-man roster this past winter, and like De La Rosa, he's already 25. Given that, it's easy to be worried he's not going to become the major-league outfielder many hoped he would be back when he was mashing in the lower minors: Brentz batted just .264/.312/.475 last year for Pawtucket, and is hitting .192/.311/.327 to this early point in 2014.
While I'm with you on worrying, especially given my generally cautious attitude towards a player I've long considered to be a future lefty masher with an arm rather than a starting outfielder in the bigs, there's a reason for optimism buried in that horrid line: Brentz has walked nine times already, against just 12 strikeouts (a 19 percent rate). If he's finally taking a step forward with his plate discipline, then the power and average should come with time. It doesn't mean he's going to be a starting outfielder for the Red Sox, but it makes his chances at a big-league career much better, especially if he can keep it up for more than a couple of weeks.
Drake Britton, LHP
Britton is major-league ready, but with Andrew Miller, Craig Breslow, and Chris Capuano already filling the lefty quota in Boston, Pawtucket was the only place for him to go. That's not a bad thing, though, as he's a more than capable depth option in the present, and didn't spend all that much time in Triple-A last summer to begin with thanks to injuries in the Red Sox bullpen. In fact, he's already thrown more innings in relief for the PawSox in 2014 than he threw total frames for the 2013 version, and he was still starting at that point.
Like De La Rosa and Brentz, Britton is also 25, but he's also had some success in the majors that came after Tommy John surgery, rather than before it, and is mostly in Pawtucket because it's the place where he'll get the most opportunities to pitch. Should another lefty go down, Britton will likely get called to Boston, as the Brandon Workman plan was to keep him starting once he began that process for Pawtucket. If nothing else, having Britton to promote and demote will make 2014 easier on the other arms who have more need of their time in Triple-A.