OAKLAND -- The Rays put right-hander Diego Castillo on the injured list Sunday and sent him back home after he complained about right shoulder discomfort following one inning of work Saturday against Oakland.

The A’s scored twice and handed Castillo the loss in a 4-2 game.

“It’s not something he’s been dealing with,” Rays’ manager Kevin Cash said Sunday morning. “It’s just something that cropped up yesterday.

“But he’s so important to us, and we’ve got to get him right. He wasn’t going to pitch [in Minnesota], and when you say your arm is bothering you, your shoulder is bothering you, we’re going to shut you down for a little bit. Hopefully, we’ll get some good news and some rest will maybe get some inflammation out of there, and he’ll be ready to go.”

As of mid-June, Castillo had a 2.05 ERA, but he has allowed eight runs in 3 2/3 innings in four games since June 16. Six of those runs came in the first and third games of this four-game matchup with Oakland, after which his ERA is at 3.93.

Wood back in Majors

Taking Castillo’s spot on the roster is right-hander Hunter Wood, who has been up and down the last two years and who is joining the Rays for the third time this season.

Wood, who was on the roster to start this road trip, is a hard thrower who has a 2.11 ERA and a 1.172 WHIP in 13 games this year, 11 of them out of the bullpen.

“He has thrown the ball well for us this year,” Cash said. “In his last outing in Triple-A, the reports were 94, 96 mph. I think Hunter, every time he comes up, he’s building confidence. We’ll stick him in whatever role is needed. Right now, we’re just trying to win a game. We’ll pick the best matchups.”

Notable

• Third baseman Yandy Díaz (right hamstring discomfort) is getting close, and both he and the club are optimistic he’ll be able to come off the injured list Thursday. He has done running and sprinting, and his injured hamstring seems to be holding up well.

• Right-hander Tyler Glasnow
(right forearm strain) played catch Sunday and is set to throw a full bullpen in Minnesota. It will be his third bullpen session since he went on the IL on May 11.