He was a disaster last season yet came back and has put himself together. A lot of people are worried about a "Craig Hansen" like break down but if thats the case then the team will go in a different direction and probably look to move him. I'm not worried about his psyche only his ability to hit corners with his fastball.
First thing, does he get brought up when the Double-A season concludes? Second, does he have an innings limit he needs to stay under? Third, can he gain Francona's confidence (hard to do) in a short period where he can actually make a difference?
A lot of questions with only 30 or so games left but I think he can be an excellent case for a secret weapon moving into crunch time. Papelbon, Oki, and Masterson have brought the bullpen up a notch from where it was a month ago but add one more stopper and we have a better looking bullpen than we did this time last season.