Closer Jonathan Papelbon is happy and locked in with a one-year deal after three straight All-Star seasons. But the front office also retained Javier Lopez, Justin Masterson, Manny Delcarmen and Hideki Okajima from last season's bullpen while adding quality arms Ramon Ramirez and free agent right-hander Takashi Saito to the mix.

It's a collection of power throwers and successful specialists, and there's depth there as well if injuries or ineffectiveness strike, as they often do in the volatile world of major league bullpens.

"I don't think we have had this much depth in the past," said assistant general manager Jed Hoyer.

"I think it's something we've learned a little bit through trial and error. We've had some seasons where we got a little bit thinner, and at certain times it hurt us. Certainly, a priority of ours going into the offseason was to make sure we had enough depth to get through a whole season."

Hoyer added that it behooved the Sox to pour on the additional depth because Boston's pitchers have embarked on journeys deep into October in each of the last two seasons, logging a good deal of innings and wear and tear.