Byron Buxton was not in the Twins lineup for Sunday’s 7-4 victory over the Yankees, and manager Paul Molitor expressed concerns about the rookie outfielder’s recent at-bats.

Over his past 12 games, Buxton is 4-for-40 with one homer and three RBI. What’s troubling to the Twins is that the strikeout bug has returned. Over his past 43 plate appearances, he has struck out 19 times, including seven times over the first three games of the series against the Yankees.

“You can see the wheels spinning and the at-bats are speeding up here again in the short term,” Molitor said. “It seems like when he does get something to hit and he recognizes those pitches, he is fouling them off. Generally early in the count, the first couple of pitches.

“Then he goes into battle mode. And you can see him almost trying not to strike out rather than thinking of how he is going to get a hit here as the count gets deeper.”

Buxton was batting .156 when he was sent down to Class AAA Rochester on April 24. He returned May 31 with a leg kick and renewed confidence. After going 10-for-23 in his first six games back, Buxton has cooled off.

In the 17 games before his demotion, had 24 strikeouts. In 18 games since his return, Buxton is batting .222 with 25 strikeouts.

“We’re just backing him off a little bit,” Molitor said. “He’s done a lot of good things since his return, but we all see what’s been happening the last couple of days.”

Sano works out

Outfielder Miguel Sano went through running and agility drills in the right field corner of Target Field between Monday’s high school state championship baseball games.

Sano, on the mend from a left hamstring strain, is getting close to being sent out on a rehabilitation assignment. The Twins wanted him to test the hamstring through a full speed workout before greenlighting his departure.

Once Sano is ready to be activated, the Twins might have an interesting decision on their hands. Robbie Grossman has played well in left field since being called up on May 20, and rookie Max Kepler, who has filled in for Sano in right, is on a six-game hitting streak. Buxton and Danny Santana are available in center.

Rosario watch

Since being sent to Rochester on May 18, outfielder Eddie Rosario is hitting .339 with four home runs and 19 RBI, after he went 2-for-4 a double and with two RBI Monday against Columbus. In 29 games, he has walked five times and struck out 16. The Twins are encouraged that all five of those walks have come in the past 10 games, a signal that Rosario is understanding the importance of better plate appearances.

“That’s part of what we told him,” Twins General Manager Terry Ryan said. “You have to go down there and take quality at-bats. Part of that is taking a walk when they want to give it to you. He’s been more selective.”

Rosario, 24, was demoted after batting .200 with three walks and 31 strikeouts in 32 games with the Twins.