The market for starting pitching at the trade deadline is still pretty weak because there are a lot of teams still in contention for the playoffs, but the Orioles seem to be one of the teams already facing elimination. They also have one of the best starters that could be available.
The Orioles would love to have Guthrie be their ace on a contending team, but he probably won't be with the team at that point. Guthrie is still under team control through 2012, but will be 34 as he enters the 2013 free agent market. That said, he can provide a contender a great pitcher that can go deep into games and save the bullpen.
Guthrie has reached 200 innings in each of his last two seasons and is on pace to do it again. He is 3-9 this year, but that has more to do with his terrible run support than his talent because he has a pretty good 3.93 ERA.
The O's aren't looking to trade Guthrie because their younger pitchers haven't developed as expected. Chris Jakubauskas is already in the rotation and Brad Bergesen or Chris Tillman would have to step up and take Guthrie's place. Both of them have had trouble with pitch count, so replacing Guthrie's bullpen saving outings would be difficult. The demotion of Brian Matusz also means that the Orioles want to keep some depth.
Guthrie is the Orioles best trade chip, so they will listen to offers, but they would need to be blown away to make a deal. Here are some possible scenarios that would get Guthrie to a better situation.
Note: All of these potential deals are purely speculative.