Valencia was optioned to Rochester on May 9 after struggling with the Twins, as he hit .190 with a homer, triple and five doubles in 100 at-bats.
He's been faring better in the Minors, as he entered Monday hitting .268 with two homers and three doubles in 56 at-bats. He overcame an early slump and is hitting .325 with a .341 on-base percentage and .525 slugging percentage over his past 10 games.
"He's doing fine," Gardenhire said. "He's putting some good swings on the ball. He hurt his wrist, but got back at it. So he's hanging in there pretty good. He's driving the ball. I've watched a couple games and saw him bang one off the center-field wall on an 0-2 fastball."
Gardenhire added that Valencia has continued to make progress with his defense, which wasn't his problem in 27 games with the Twins this season.
"He was fine here and was a lot better and working hard at it," Gardenhire said. "We asked him to do that and he's been doing fine down there."