Royals third baseman Mike Moustakas sat out again Sunday with a sore knee, the lingering effects of a bone bruise he suffered July 28 in Seattle.

“It’s not a major issue. It’s a playable thing, but it’s going to be sore for a couple weeks,” said manager Ned Yost. “Just pick your opportunities to give him breaks when you can.”

Moustakas sat out Friday and Sunday against Rangers lefties Matt Harrison and Derek Holland, respectively, but played Saturday against right-handed Scott Feldman.

“You don’t want to get it to the point where it gets unplayable, so you take opportunities against tough left-handers and give him a day to sit in the training room,” Yost said. “It helps it a great deal when you can take a break and get four or five treatments on it and come back the next day and it feels a lot better.”

John Lamb to return

On Aug. 14, left-handed pitching prospect John Lamb will make his first start in the Surprise Arizona Rookie League since having Tommy John surgery last year.

Lamb, a 22-year-old who was a fifth-round draft choice in 2008, underwent surgery on June 3, 2011, after just three starts at Class AA Northwest Arkansas. Lamb was given the Paul Splittorff Award in 2010 as the best minor-league pitcher in the Royals system, posting a 10-7 record with a 2.38 ERA in 28 starts.

Cain’s power

Outfielder Lorenzo Cain has swung a big bat since he returned from the disabled list July 13, and it has led to a new perception of him as a power hitter.

Entering Sunday, Cain was hitting .325 with 17 RBIs and eight extra-base hits in 22 games since coming off the DL.

“I think he’s going to be a middle order of the guy,” Yost said. “He’s hitting third right now because he’s given us some production. … He’s got power.”

In 49 combined games with the Brewers and Royals in 2010 and 2011, Cain never batted third, fourth or fifth in the order. Since his return from the DL this year, however, Cain has batted there in 19 of his 20 starts, and has been the No. 3 batter for 12 straight starts.

“He can hit the ball to all fields,” Yost said. “I imagine he’ll be a middle of the order guy when it’s all said and done.”

Sanchez to DL

Colorado Rockies and former Royals pitcher Jonathan Sanchez has been placed on the 15-day disabled list with left bicep tendonitis. Since being traded to the Rockies last month for Jeremy Guthrie, Sanchez is 0-3 in three starts with a 9.53 ERA in 11.1 innings.