The Nats may very well have an abundance of pitchers next season. Shocking but if there are no health scares, that is what we are looking at. Strasburg, Zimmermann and Lannan appear to be locks for the rotation based on past performance. Detwiler is making a case for a spot. Peacock and Milone are both showing strongly enough in AAA that you expect them to be given shots to make the rotation next Spring. Let's not forget about Maya. That's 7. If they re-sign Wang (which really why put all that money into him if you aren't going to?) that's 8. (we'll leave out Livan for now, and consider Cole, Solis, Ray, Purke, Meyer 2013 questions at best).
Eight pitchers is obviously too many for a rotation. Normally I'd say just keep them all. Injuries and developmental issues turning this 8 into a 5 would not be a surprise. However this isn't a normal offseason. The Nats are looking to turn a corner into something resembling a playoff caliber team and it would really help them do that if they could get a dependable CF. Teams just don't deal CFs for nothing though and any deal made in the offseason will almost certainly involve a young starter. The question then becomes who do you deal?
Maya and Wang are off the table. No one would consider 30yr old Maya worth trading for and if they want Wang they can go after him in FA. Strasburg and Zimm are off the table too for obvious reasons. That leaves Peacock, Milone, Lannan, and Detwiler.
Lannan and Detwiler have clocks ticking on them, though the clock for Lannan is a lot louder. Lannan is arbitration eligbile and will be a free agent in for the 2014 season. Detwiler is just about to become arb eligible and will be a FA in 2016.
John's also the oldest, but the gap isn't as big as you might think. He'll be an old 27 next year, Detwiler a young 26, Milone 25, Peacock 24.
And to put John even further ahead - he has arguably the worst peripherals in the group. He walks too many and doesn't strike out enough. Detwiler is going to get you more Ks. Scouts argue on whether Milone's stuff can fool major leaguers, but there is no arguing with his pinpoint control. Peacock has the best "stuff", pure and simple. It's a matter of harnessing it.
So you trade the oldest, arguably least talented guy right? Especially since he's the closest to FA, right? Well, here's the thing. John has something the other 3 don't have. He has three things really. 2008, 2009, and 2011 (and parts of 2007 and 2010 if you like). He has repeated major league success. After a year, or maybe two, you could argue that it wouldn't be repeated. It's much harder to do now since he's repeated it again and again. Trading John is trading a known. It's a known #4 type starter, but it's a known. Peacock, Milone, and Detwiler are all various shades of unknown. Detwiler might break down again. Milone's stuff might not be good enough. The batting eye of the major league hitter might make Peacock throw 90 pitches in 3 innings. They aren't guarantees. Going into a time when you want to make strides, don't you need guarantees? Isn't that why you give a set-up man X million a year? Because you feel slightly better on his chances to provide you with the performance you want?
It's a silly exercise because really who knows if the Nats will trade and with whom? And what do they want? But silly doesn't mean it isn't fun. What do I do? I hope Detwiler kills it from here on out and then I deal him. 8 or so starts would be a nice run but it's not even a third of a season.