MESA, Ariz. -- Right-hander Sonny Gray has been diagnosed with a moderate lat strain and won't throw for at least three weeks, leaving the A's without their ace come Opening Night.
Gray is barely removed from the worst year of his career, having nursed two separate injuries that required extended time on the disabled list. But the 2015 American League Cy Young Award finalist came to camp healthy and was ready to put those woes behind him, making Thursday's news all the more disheartening.
"It's very disappointing for him," A's manager Bob Melvin said. "He came to camp ready to go, worked as hard as he's ever worked even though he's a hard-working kid to begin with, was very positive, the stuff was really good. This is another setback, and he's going to have to deal with it, as we are."
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According to Melvin, Gray felt the injury after his last start against the D-backs on Tuesday, when he allowed seven runs in two innings, but "didn't feel like it was a big deal."
"It got him a little bit," Melvin said. "He wasn't expecting to hear what he heard yesterday. It's a bigger deal than we thought, so it surprised him."
Gray's temporary absence -- the A's hope to have him back by the end of April -- opens up an opportunity for right-hander Kendall Graveman to make his first career Opening Night start. Graveman essentially anchored the staff while Gray stumbled to a 5.69 ERA during an injury-marred 2016 season, and he'll have young company behind him, leading with Sean Manaea, who pitched well in a 12-5 victory over the Reds on Thursday, and Jharel Cotton, who will start Friday against the Royals.

Melvin has no shortage of options to fill the final two rotation spots. Jesse Hahn and Andrew Triggs are the leading candidates, though the A's will also consider Raul Alcantara and Daniel Gossett.

"We definitely have arms that can step in, but you're missing your ace," catcher Stephen Vogt said. "There's no getting around that. He's the anchor of the pitching staff. Obviously, we do have some young, exciting arms and some guys hungry to step in, but you can't really replace somebody like Sonny."
"You don't expect to get tested like this right away," Melvin noted.
Last year, Gray missed his Opening Night start because of food poisoning and was limited to 22 starts in all because of his first career DL stints -- first, for a strained trapezius, then a strained forearm.