Starters in the Bullpen

Matt Cerrone at MetsBlog.com brought up an intriguing thought this morning about starters coming out of the bullpen. Jerry Manuel remarked that he was not opposed to bringing starters out of the bullpen on their designated throw days to potentially pitch an inning or two.

Cerrone brought up the fact that if the Mets are willing to do this, and today is Pelfrey's throw day, why not have Pelfrey pitch the first inning and then bring in Santana to pitch the final 8 innings?

Now I'm sure there's a reason that this wouldn't work, but I'm not sure what it is. Having never been a major league pitcher I'm sure there's a different psyche involved coming into a game rather than starting it, but I think this point has merit.

If Pelfrey can throw 20 pitches and then Santana can come in a finish it out, why wouldn't the Mets want to do this? Santana is notorious for giving up first inning run (and home runs) so why not let him come in a pitch the second inning on? He'd still get the win, but it buys the Mets an extra inning without having to turn to the bullpen?

I'm sure there's an explanation for why a team wouldn't do this, but at this point it'd have to be pretty convincing to make me think otherwise.