The big thing with Roy Oswalt is this. Will Houston eat much of his contract for much-needed pitching depth in their farms or are the Nationals going to have to pay him $15M in 2010 and $16M in 2011? He has a $2M buyout for 2012. If the Nats can get the 'Stros to eat the money, then I say go for it. We won't miss who we give up, we have a BOATLOAD of pitching in the farms. That's exactly when you stock the farms with pitchers so you can make trades like this. But ultimately, Oswalt wants to go a contender and the Nats haven't proven they are one yet. Maybe if you straighten themselves out, they could be contenders around the All-Star break.
Things could get very exciting for the Nationals after the All-Star break. They should be getting Jason Marquis and Chien-Ming Wang back from injury, adding two proven winners to that rotation. And of course, Strasburg will have been in the rotation for about a month at that time. Also, Jesus Flores should be close to returning although he would only supplant Wil Nieves as a backup catcher behind Pudge Rodriguez.
After the All-Star break, the Nationals will have a surplus of starters and with Oswalt, might have a logjam in Triple-A Syracuse.
Look at this potential rotation post-All Star break:
6. Livo (I think he might accept moving to the bullpen as a long reliever.)
With Oswalt in the rotation, I don't know what to do with either Lannan or Olsen, who might get bounced out of the rotation. If the Nationals ever carried 7 starters that would sure give them a lot of firepower down the stretch.
Consider if they happen to clinch the wild-card, here are the postseason stats of the Nats potential starters:
Livan Hernandez: 10 starts (7-3), 3.97 ERA
Jason Marquis: 3 starts (0-2), 4.56 ERA
Roy Oswalt: 4 starts (4-0), 3.66 ERA
Chien-Ming Wang:4 starts (1-3), 7.58 ERA
Including Oswalt, the Nats will have four pitchers with post-game experience, without him, they still have three. As you can tell from the stats, these three pitchers (besides Oswalt) don't spell a sweep through the Wild Card but if the Nationals got there, they could put pitchers on the mound with experience. Pair that with a handful of Nationals fielders with postseason experience and the Nationals have a reason to believe if they make it, they can go somewhere.
This is all just some food for thought. The Nationals need to step it up and play lot better baseball than they have lately if they want to win the Wild-Card and go to the playoffs for the first time in franchise history.