SAN DIEGO -- Miguel Sanó's comeback lasted three games -- but now, the slugger is headed back to the injured list.

An aggravation of Sanó's left knee injury resulted in his placement back on the 10-day IL before Saturday's game against the Padres, along with Max Kepler, who will be sidelined with a fractured fifth toe in his right foot that the Twins initially hoped he could play through.

In corresponding moves, the Twins recalled outfielder Mark Contreras and selected the contract of infielder Tim Beckham from Triple-A St. Paul.

"I feel sad," Sanó said of heading back to the IL so soon after returning. "It was a lot of work and I put a lot of effort every day into trying to come back and play my game. And it's not easy for me. I gave it every chance, and to God, thank you for everything. I'm still working to try to get better. It's all I can do."

Though Sanó said he had recovered from the torn meniscus in his left knee sustained during a celebration on April 26 that eventually required surgery, he started feeling soreness in the area again following a slide into second base during the final game of his rehab assignment with Triple-A St. Paul on July 23, when he singled twice and homered.

The Twins aren't sure about the exact nature of the injury and expect to know more after Sanó undergoes MRIs in Minneapolis on Monday.

"We haven’t done any imaging yet," Twins manager Rocco Baldelli said. "It’s not like we know exactly what it is. It sounds like something that’s pretty similar to what he was dealing with."

He initially felt he could play through the injury and was brought up to the Twins on July 26 following a 75-game absence, but saw the soreness and inflammation persist to the point where he didn't feel like he could continue playing after Friday's game, Baldelli said.

Sanó was 0-for-6 with four strikeouts in three games since his return to the Twins. As a whole, he's hitting .083/.211/.133 (5-for-60) with a homer and four singles in 20 big league appearances this season.

The slugger's spot in the Twins' first-base rotation was already somewhat tenuous considering the continued productivity of Jose Miranda and Luis Arraez, who will otherwise platoon at the position. Now, with Sanó facing another shutdown and buildup, it's fair to wonder if he could be done for the season -- which would likely end his time with the Twins -- but the Twins aren't thinking that far ahead yet.

"For me to comment on that with any certainty, it’s hard to do, but we’re hopeful that he can get himself into a good spot sooner than later," Baldelli said. "But we have a lot to figure out first. There’s no way to draw a plan up until you know what you’re dealing with, so that will be the first step, but ... we’re still in July, so we still have a ways to go. Could he find himself back out there? Absolutely."