The A’s will enter the regular season not knowing when starter A.J. Puk will be available to pitch.

Following a meeting with shoulder specialist Dr. Neal ElAttrache on Monday in Los Angeles to look over a shoulder strain that landed him on the injured list, Puk received a PRP cortisone injection to alleviate inflammation in his left shoulder. After a 48-hour rest period, Puk will resume playing catch. But A’s manager Bob Melvin said there is no timetable for a return.

“He’ll rest for 48 hours and just go through a ramp-up for probably two weeks,” Melvin said. “It’s going to be a little bit of time before we see him. They’re not going to push him for two weeks, no matter how good he feels in that period of time.”

Puk, Oakland’s No. 3 prospect per MLB Pipeline, was set to make his first Major League start next Tuesday against the Rockies at the Coliseum. That spot will now be filled by right-hander Daniel Mengden.

Luzardo ready to pitch in games

After facing Ramón Laureano in a live batting-practice session before Monday’s exhibition game against the Giants, Jesús Luzardo was deemed ready for game action by Melvin. Luzardo, Oakland’s No. 1 prospect, will begin the season in the bullpen and could see action in the first or second game of the A’s opening four-game series against the Angels, which begins Friday night at the Oakland Coliseum.

Decision at catcher looms

The A’s will make a decision on their catching situation following Tuesday’s exhibition game against the Giants. With three rookie catchers in Sean Murphy, Austin Allen and Jonah Heim each impressing during Summer Camp, Melvin was unsure if all three would make the Opening Day roster but said he expects all three to contribute to the big league club at some point in 2020.

“However it works out, we feel comfortable with all three,” Melvin said. “We’ll make a decision on that later today. But my guess is, whoever is not part of the group, we will see at some point in time. We go through 45 to 50 players a year. It’s a luxury to have three young catchers we feel really good about.”

Payton returns to A’s

The A’s received an unexpected surprise on Tuesday when outfielder Mark Payton, who was selected by the Reds in the 2019 Rule 5 Draft, was returned to the club.

Payton had a monster year at Triple-A Las Vegas last year, batting .334 with 30 home runs and 97 RBIs. He was added to the A’s player pool that is training at the team’s alternate site in San Jose, providing more outfield depth for the organization.

“We’re happy to get him back,” Melvin said. “You look at his numbers last year, just how he handles the bat and plays defense, there are a lot of things to like about him. I’m kind of surprised we got him back. But once we were given that option, we were eager to get him back. Vegas plays into some of the home run numbers, but this is a good player who has been in our organization and knows how we do things. We’re happy to have him back.”