Atlanta — Orioles manager Buck Showalter said infielder Tim Beckham’s activation from the disabled list after two months out for core muscle surgery could come as soon as today, creating what he hopes is the good kind of problem with his daily lineup card.

Beckham’s return today, which Showalter said “was the hope and the plan” as he prepared to play Sunday for Triple-A Norfolk, will mean the Orioles will be challenged to find enough lineup spots for all of Beckham, Danny Valencia, Mark Trumbo, Chris Davis, Trey Mancini and Colby Rasmus between the corner infield and outfield spots plus designated hitter.

Showalter said the Orioles have a plan, “which will be revealed to us in time.”

“We’re looking forward to getting Tim back. It’s been a long time. We’re hoping to get him back to the player he was when he originally came over [in a trade with the Tampa Bay Rays on July 31]. I’m hoping this surgery and some of the things can help him.”

Beckham, who had a torrid first month with the club last season, was batting .179 with a .529 OPS when he underwent surgery in late April to repair a long-standing groin injury. He’s played both third base and shortstop over his rehab stint, and has three hits in seven games entering Sunday.

In his absence, Valencia has taken over as the regular third baseman. He’s known for his bat more than his glove, and his .283/.350/.483 batting line with six home runs has earned him an everyday role. After Saturday’s win over the Braves, Showalter said “Danny has been sharp at third base for us,” as his defense played a big role in the Orioles holding on in a game that got tight down the stretch.

Beckham coming back at third base could force Valencia to shift back into a designated hitter/first base role, but he’s performed far better than just as a platoon player who hits left-handers, and those spots are already full for the Orioles.

Showalter has said Davis will play every day now that he’s back from his swing-rehab sessions with Brady Anderson, and Trumbo is riding a seven-game hitting streak that has coincided with the team’s best offensive stretch of the season. Trumbo has featured significant statistical splits between when he plays the field versus being the DH, and his recent surge came as he played plenty of first base and outfield in National League cities.

But now that Rasmus is back from his long-term hip injury and playing well in a small sample, and Mancini continues to get every opportunity to work his way out of his sophomore slump, the Orioles will have a hard time finding regular at-bats for everyone. Jace Peterson, who has played well of late, also will warrant consideration in that mix.

Mancini returns with homer: Mancini, who pinch-hit Friday but hadn’t started since Wednesday because of a stiff neck, was back in the lineup Sunday after Showalter gave him Saturday to clear up his last bit of soreness.

“Trey should be good to go,” Showalter said. “He was OK yesterday, I thought. But I tried to give him one more day. Anybody that’s ever had a stiff neck knows it doesn’t go away overnight.”

He rewarded the team with a home run — his 10th of the season — and the team’s only multi-hit game. Mancini said the time off might have interrupted his quest to get back on track, but had plenty of benefit.

“I’ve been working on some things, and kind of was set back slightly with the neck the last few days,” Mancini said. “The silver lining in that was I got a few days off and my knee has felt as good as it has since I slid into the wall [April 20]. If you want to look at it in a positive way, I guess that’s it. But it’s a long process.”

With Rasmus starting a second straight day, Mancini takes an outfield start from Trumbo, who missed time last month with a knee problem that Showalter said was cropping up again. He appeared in the fifth inning as a pinch-hitter, hitting a two-run home run to give him five home runs in his past seven games.

Sisco getting going: Catcher Chance Sisco started for the second time in four games since he was optioned to Norfolk on Saturday, collecting two hits. Showalter said Sisco would play regularly after the team sent him down after some struggles at the major league level.

“I think he’ll catch the majority of the games down there,” Showalter said. “He’s catching like he’s supposed to be. He had a good game yesterday — swung the bat well, threw well.”

In two games since he was optioned, Sisco has allowed six successful stolen bases.

Ynoa’s shinsplints: Showalter said right-hander Gabriel Ynoa, who has missed most of the season with shinsplints and then shoulder soreness, didn’t make his third scheduled rehab start for Double-A Bowie this weekend because the shinsplints returned.

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