A’s: Starter Gray “tested” by lat injury.

MESA, Ariz. — Sonny Gray spoke to the media Friday for the first time since being diagnosed with a lat strain that is expected to keep him out until late April.

“Sometimes you get tested, and there’s not a reason for it,” the A’s right-hander said, adding that he’s thought 100 times about what might have led to the lat strain with no answer. “But there’s no doubt in my mind that when this gets knocked out, I’m going to be back to being the guy I’ve been.”

Gray, 27, has been focused on being fully healthy and getting back on track after a rough 2016 season, his worst in the majors. He said he’d been feeling fantastic and didn’t even think there was an issue when he felt some tightness during and after his start Tuesday. But he mentioned it to team trainers, who scheduled an MRI exam.

“I told (manager) Bob (Melvin) ‘I’m not worried about it, it will be fine,’ and then next day I find out that there’s a little strain there that will take a little while to heal — which was kind of shocking to me,” Gray said.

There are a few positives, however. First, it’s not an arm injury. Second, it happened with three weeks left in the spring, so instead of missing 5-6 weeks of the regular season, he might just miss three weeks. And getting an MRI exam prevented the possibility of a worse strain, one that might have cost Gray months.

“I’ve heard this is the best of a worst-case scenario,” he said. “I’m in great shape, my arm feels amazing, my body feels amazing and then this little thing kind of limits you a little bit, that is what’s most frustrating.”

Briefly: Melvin returned to the Bay Area on Friday to attend to a personal matter, and bench coach Mark Kotsay will handle managerial duties in his absence. “Bob is meticulous in preparation, so everything is status quo,” Kotsay said. “We have our work day planned, the lineup was already set. I’m just filling in until he gets back.”…

Angela Sun has been hired as CSN California’s A’s in-game reporter.