2:49pm: Athletics assistant GM David Forst tells reporters, including MLB.com's Jane Lee, that Kazmir's injury is very minor, and he could have pitched today (Twitter link). Slusser tweets that Kazmir may even start tomorrow.
Forst also adds that the team has no plans to look outside the organization to acquire additional pitching depth (Joe Stiglich of Comcast SportsNet reporting via Twitter).
It's a big blow for the defending AL West champions, and though the team has more pitching depth than most clubs, they also shut right-hander A.J. Griffin down for three weeks over the weekend and will likely be without him for at least the first month of the season, per the San Francisco Chronicle's Susan Slusser (on Twitter). Beyond that, offseason signee Scott Kazmir was scratched from today's Spring Training start due to triceps stiffness.
With Parker and Griffin on the shelf, the A's would figure to open the season with Kazmir (if his triceps injury is minor), Sonny Gray, Dan Straily, Tommy Milone and one of Drew Pomeranz, Jesse Chavez or Josh Lindblom in the rotation (Slusser earlier tweeted that it would likely be Chavez). Obviously, that's a considerably weaker group than it would be with a healthy Parker and Griffin in the mix, and it's fair to wonder if the A's will pursue a trade to add further depth — perhaps an out-of-options starter from another club.
Parker, 25, has given the A's 378 1/3 innings of 3.73 ERA ball with 6.5 K/9 and 3.0 BB/9 over the past two seasons, helping the club to a pair of AL West division titles. Oakland originally acquired him from the Diamondbacks along with Ryan Cook and Collin Cowgill in the trade that sent Trevor Cahill and Craig Breslow to Arizona. His first Tommy John surgery came back in October 2009 when he was still in the Diamondbacks organization.
The news is the latest in a slew of Tommy John surgeries, as Kris Medlen is all but certain to require Tommy John, while Brandon Beachy also faces that possibility and Patrick Corbin will seemingly suffer that same fate as well. Beyond that, Padres right-hander Joe Wieland is undergoing an MRI today that could reveal UCL damage and lead to his second Tommy John operation.