The All-Star righthander suffered a strained latimus muscle in the back of his pitching shoulder.

WEST SACRAMENTO, Calif. − Pablo López threw a warmup pitch before the sixth inning Tuesday, and then a couple more. Then he stopped and considered all the ways the next few minutes might go. Maybe he’d be fine, maybe he’d pitch another scoreless inning.

Or maybe not.

“In my head, I’m like, ‘Well, if it feels [sore], if I tried to make a max-effort pitch to get the inning started, who knows what could happen?’” the Twins righthander said after a 10-3 victory over the A’s. “Those split-second scenarios where you start hearing both sides. ‘Oh, just power through it, it’s nothing,’ or ‘it could be something terrible.’”

Prudence prevailed. López called for the trainer, left the game and walked to the clubhouse. And eventually came the news that López and the Twins feared: He suffering a strained latimus muscle in the back of his pitching shoulder.

López will undergo a more extensive examination on Wednesday, but he sounded resigned to his first stint on the injured list as a Twin.

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“Just having an understanding of the [shoulder] area, what goes on back there, it feels like if I were to do a lat pulldown, I would be like, ‘Yeah, that doesn’t feel too good,’” he said. “The one thing we don’t know is how severe it is. Obviously tomorrow, imaging, doctors’ opinions, getting looked at, and we’ll see what the plan moving forward will be.”

López, who was credited with his fifth victory Tuesday and owns a 2.82 ERA, first felt a tightness behind his shoulder during the fifth inning.

“The [Brent] Rooker at-bat, the second pitch was an 0-1 sinker that kind of sailed on me. Right at the very end, I felt something tighten up on me,” López said.