ST. LOUIS -- Six Northwest Arkansas players have been selected for the Texas League All-Star Game on June 28 at Tulsa.

Selected as starters for the North Division were first baseman John Whittleman, designated hitter Christian Colon and outfielders Yem Prades and Carlo Testa. In addition, left-handed starting pitcher Justin Marks and right-handed reliever Patrick Keating were named to the team.

Colon, who has been playing shortstop and second base for the Naturals, has a toe injury and will be not be able to play. He's been replaced by Naturals infielder Mario Lisson.

Tying blast makes Butler look like pro in pinch

ST. LOUIS -- Maybe now Billy Butler is getting the hang of this pinch-hitting gig. Nothing like a last-ditch, game-tying home run to help the learning curve.

With the designated hitter eliminated on National League turf, Butler found himself in a pinch-hitter's role for the Royals in St. Louis. (Moving Eric Hosmer from first base to right field for two games at Pittsburgh and keeping Butler in the lineup at first base exposed defensive shortcomings, so manager Ned Yost decided to platoon the two at first base in NL cities.)

"It's new. I do a little bit each year. It's definitely not an easy job. You get one chance to do it and you've just got to act like it's a normal at-bat," Butler said before the Royals' 15-inning, 5-3 victory over the Cardinals on Sunday.

Butler is an advanced student of the hitting art but, normally an everyday player, he claimed he hadn't quite mastered the nuances of pinch-hitting.

"When I get it figured out, I'll tell you," Butler said. "I've haven't done it enough to even know how to do it."

Until Butler, batting for Humberto Quintero, blasted Jason Motte's 0-2 pitch out of the park to give the Royals a 2-2 tie on Sunday, he had never hit a homer or driven in a run as a pinch-hitter. This was his 30th pinch-hitting appearance and made him 7-for-26 (.269).

On Monday night at Houston, Yost said that Butler would be back at first base against left-hander J.A. Happ with Hosmer in the bench role. Hosmer's career as a pinch hitter? He's 0-for-1.

Maybe he can seek out Butler for some tips. Billy seems to be getting the hang of it.

Royals haven't set date for Perez's return

ST. LOUIS -- Catcher Salvador Perez's rehabilitation assignment with Triple-A Omaha continues to go well, but there's no date set for him to join the Kansas City club. He's missed all of the regular season following left knee surgery in March.

"Probably won't see him during this trip," manager Ned Yost said before Sunday's series finale against the Cardinals.

Perez, in his first nine games for Omaha, batted .333 (13-for-39) with two doubles and seven RBIs.

"I don't care what he's hitting, I just check the health of his knee," Yost said. "He feels great after every day. He caught seven innings in the first game of a doubleheader [Saturday] and he'll catch nine innings [Sunday]."

Center fielder Lorenzo Cain, out since the first five games of the season, will begin a new rehab assignment on Monday with Double-A Northwest Arkansas. He was playing for the Naturals getting over a groin strain when a torn hip flexor dealt him a setback.

In addition, catcher Manny Pina, out with knee surgery, is to begin a rehab assignment soon.