Garrett Mock (and the Nationals bullpen)

After reading my post on bottom end National League closers, Anonymous wanted to know about one more team's bullpen:

What do you think about Garrett Mock, who is supposed to be brought up Monday? I know the Nats have been grooming him as a closer, but he struggled at Syracuse. Could he step in and close right now?

For starters, Mock is a very good prospect long term, and should be part of the Nationals long-term plans.

He spent almost his entire minor league career as a starting pitcher, and wasn't moved to the bullpen until he was called up to the majors last year. He's a pitcher you wouldn't have noticed if you simply looked at his minor league ERA/WHIP, but someone you would have noticed if you looked at his K/IP. A poor 2007 knocked at AA Harrisburg knocked Mock off of the prospect radar, but his strong 2008 put him right back up there. Conventional wisdom seems to put Mock in the bullpen, although the control issues he has had - with the exception of his poor 2007 - seem to have come mostly in the pen.

Since Anonymous wrote his comment, the surging Nationals have won two games in a row and Joel Hanrahan has saved both of them. The Nationals might be bad this year, but they're not going to go 15-147, which is what they were on pace to do after their 1-10 start). Hanrahan is in the third tier of National League closers, but he isn't terrible. Like a lot of bottom tier closers, he could definitely lose the job if he struggles, but he'd probably have to blow two or three saves in a row before that happened.

Mock is probably the set-up by default, but as Anonymous points out, Mock's numbers were very poor at Syracuse so he'll need to put together a decent string of outings in the majors before he has a legitimate shot as a CIW. Given the major shake ups in the bullpen and on the team in general, I suspect that Manny Acta is going to stick with Joel Hanrahan for as long as he can in order to infuse stability into what is otherwise a very unstable situation.