GOODYEAR, Ariz. -- A's right-hander Jarrod Parker will undergo elbow surgery on April 1, and only then will the team learn the extent of his injury and how it will affect his future.
Parker's first simulated game was cut short last week when he experienced pain in his elbow, and an MRI revealed a repeat fracture to the medial epicondyle, the same injury he suffered in May while rehabbing from his second Tommy John surgery.
It's unclear if a third reconstruction of the ulnar collateral ligament would be involved. Parker would be in select company if that occurs, and his already tumultuous path back to the big leagues would be significantly slowed should he choose to continue pitching.

"When it's done, we'll let you know, because sometimes you go in there and you're not sure," A's manager Bob Melvin said. "You can see one thing with an MRI, and once you get in there it could be different."
Los Angeles-based Dr. Neal ElAttrache, the Dodgers' head team physician, examined Parker on Tuesday and will perform the surgery. Tommy John specialist Dr. James Andrews performed each of Parker's previous three elbow operations, the first on Oct. 28, 2009.
Parker, 27, a first-round Draft pick by the D-backs in 2007, made his Major League debut in 2011, and he was a fixture in the A's rotation in 2012-13, going 25-16 with a 3.73 ERA in 61 starts. He last pitched in a Major League game Oct. 7, 2013, picking up an American League Division Series Game 3 victory over the Tigers.
Melvin spoke with Parker on Thursday, but he suggested Parker will wait until after the surgery to decide whether to attempt a comeback again.
"I'm just kinda there for him," Melvin said. "He'll open up about what he wants to do when he's ready for that. I think right now it's the surgery that's more on his mind than anything else, then we'll see where he is after they repair whatever it is they're repairing.
"He's tough. He's trying to keep it pretty narrow in how far he's looking."
Former A's pitchers Jason Isringhausen and Jose Rijo are on a short list of three-time Tommy John patients, and they are the only ones to successfully return to the Majors. Jonny Venters is attempting a comeback with the Rays after a third surgery.