The season-ending injury to Brandon McCarthy, on the heels of the season-ending injury to Adam Wainwright, means the trade market for starting pitching could move quicker than usual. Last season, Billy Beane acquired Jeff Samardzija and Jason Hammel on July 5, well before the July 31 trade deadline. Look for a similarly aggressive move this season -- if not earlier. Here some teams that could be buyers and who they may be buying.

POTENTIAL BUYERS

Los Angeles Dodgers: While statheads praised the McCarthy signing -- four years, $48 million -- it came with obvious risk considering his injury history. Now's he out with a torn elbow ligament and a rotation that has already given starts to retreads David Huff, Scott Baker and Mike Bolsinger will scramble to fill two spots until Hyun-Jin Ryu returns from his shoulder impingement. Ryu threw his first bullpen session since he was shutdown in mid-March on Sunday and will test his shoulder again on Tuesday, but there's no timetable for his return. Joe Wieland, who has seven major league starts, has a 3.00 ERA at Triple-A and is a rotation possibility.

St. Louis Cardinals: The Cardinals have the best rotation ERA in the majors, but Wainwright joins Jaime Garcia on the DL. Marco Gonzales and Tyler Lyons are in Triple-A, but neither has pitched well yet. Tim Cooney, not yet on the 40-man roster, is another option, as is reliever Carlos Villanueva, who has starting experience. The Cardinals probably aren't as desperate as the Dodgers, with Michael Wacha and Carlos Martinez currently pitching well, but losing Wainwright's workload and results is obviously huge.

Toronto Blue Jays: Minus Marcus Stroman, out for the season after tearing up his knee, the rotation has been terrible so far, with a 5.04 ERA. Rookie Aaron Sanchez was a little better on Monday, with seven strikeouts in 5 2/3 innings, but he and fellow rookie Daniel Norris have both struggled with their control at times.

Boston Red Sox: They have the worst rotation ERA in the majors at 5.84. While they have a stellar group of prospects waiting at Triple-A and Rick Porcello (6.48 ERA) and Wade Miley (8.62 ERA) can be expected to improve, you get the feeling they'll make a move at some point.

Baltimore Orioles: The rotation hasn't been good, with Chris Tillman and Bud Norris both struggling. The Orioles have options, but Kevin Gausman has been mediocre in relief and Dylan Bundy has pitched just nine innings in three starts in Triple-A.

Seattle Mariners: Hisashi Iwakuma just landed on the DL with a lat strain, and youngsters Taijuan Walker and James Paxton haven't produced yet. They'll give those two time to get straightened out -- Walker gave up only an unearned run in seven innings Monday against the Rangers -- but if they don't, the Mariners might have to do something.

Houston Astros: Dallas Keuchel and Collin McHugh are a nice 1-2 combo, but the back of the rotation could use an upgrade.

Now for the tricky part: Which pitchers might be available? Obviously, we all know about Cole Hamels, although he'll have to start pitching better for the Philadelphia Phillies to get what they would want for him.

A few other possibilities ...

Johnny Cueto, Cincinnati Reds: He'll be a free agent and likely out of the Reds' price range, so the Cy Young candidate is clearly the biggest name out there. Of course, the Reds have to fall out of the race before they'd trade him; even then, with Cincinnati hosting the All-Star Game, they'd be unlikely to trade Cueto before the break.

Mike Leake, Reds: He'll also be a free agent, a back-end type of starter who would fit in nicely for the Dodgers or Cardinals and wouldn't cost the premium prospects that Cueto will command in return.

Kyle Lohse, Milwaukee Brewers: The Brewers are the one team we already know is pretty much dead, and it'll likely to embark on a midseason rebuild if things don't turn around in a hurry. Lohse is in the final year of his contract. While he has been hit hard early on, he's been a reliable starter in recent seasons. Maybe a return to St. Louis?

Matt Garza, Brewers: He's signed through 2017 with a 2018 vesting option, so he wouldn't be cheap. But if the Brewers do try to rebuild, he's one of the few marketable players they have.

Tim Lincecum and Ryan Vogelsong, San Francisco Giants: It's hard to envision the Giants as sellers, but if they do fall out of the race, these two are impending free agents. Of course, if they fall out of the race, it's likely because these two haven't pitched well.

Aaron Harang, Philadelphia Phillies: The Phillies are terrible and Harang has been great so far, with a 1.37 ERA through four starts. He's not that good but he had a solid 2014 with the Braves. This is exactly the kind of player the Phillies should be looking to cash in.

Yovani Gallardo, Texas Rangers: The Josh Hamilton acquisition suggests the Rangers still fancy themselves playoff contenders, and in the wide-open AL West, you never know. But this still looks like a team that will fall out of it, which will put Gallardo on the market.