KANSAS CITY -- Right-hander Kyle Zimmer, the Royals' No. 2 prospect, according to MLB.com, shook off a slow start to the season and has pitched much better since the All-Star break at Class A Advanced Wilmington.
In his last five starts, Zimmer has a 2.61 ERA and a 42-to-6 strikeout-to-walk ratio.
Now, the Royals have rewarded Zimmer for the turnaround. The club promoted him to Double-A Northwest Arkansas on Friday. Zimmer is scheduled to make his debut with the Naturals on Saturday.
Zimmer was the fifth overall selection in the 2012 First-Year Player Draft and is ranked No. 28 on MLB.com's Top 100 prospect list. His upper-90s fastball is his best pitch, but his changeup, curveball and slider all have the potential to be above-average Major League offerings.
Even when Zimmer was struggling at Wilmington this season, hitters still had trouble making contact against him. He struck out 113 batters in 89 2/3 innings in 18 starts for the Blue Rocks and leaves the Carolina League as its strikeouts leader.
Royals still basking in their All-Star moments
KANSAS CITY -- The Royals' All-Star trio returned with plenty of memories from their time spent in New York earlier this week.
Alex Gordon, Greg Holland and Salvador Perez entered Tuesday's game in the seventh inning for the American League squad and each played a role in the 3-0 victory.
"My adrenaline was pumped as much as it was just going in there and then I saw Salvy and Greg coming in and that made it even more," Gordon said. "It was very exciting and a fun time, and we experienced it all together."
Holland retired the first hitter he faced in the seventh with some help from Orioles third baseman Manny Machado, who made a terrific play to get Arizona's Paul Goldschmidt at first. Holland allowed a single to the Mets' David Wright in the next at-bat before the right-hander made an early exit.
Gordon flied out to deep center in his lone at-bat in the ninth inning, but made a big catch in left field with Yankees closer Mariano Rivera on the mound in the eighth to assist in his final inning.
"I was going to do anything to make a catch when Mariano was pitching," Gordon said. "It kind of froze me because it was a line drive right at me, but then I knew it was over my head so I tried to make it look as easy as possible."
Perez was also a big part of Rivera's final All-Star inning, as the Royals catcher was behind the plate for Rivera, named the game's MVP, as he retired the side in the eighth inning.
"It was unbelievable," Perez said. "Those are the best 10 minutes I will never forget in my life."
For a moment, with "Enter Sandman" blasting over the speakers, Perez and Rivera were the only two players on the field before the inning started. After three quick outs, the two embraced before returning to the dugout.
Perez also singled and scored in the eighth, becoming the first Royals player to get a hit in the All-Star Game since Bo Jackson had two, including a memorable mammoth homer in 1989.
"I was real proud of all three of them," manager Ned Yost said.
It was the first time since 1988 -- George Brett, Kurt Stillwell and Mark Gubicza -- that three players represented the Royals in the Midsummer Classic.
"It was a dream come true," Holland said. "We had 30 percent of the winning All-Star team out there in Royals colors, so that was pretty cool."
Herrera amped for return to Royals' bullpen
KANSAS CITY -- Reliever Kelvin Herrera rejoined the Royals prior to Friday night's game against the Tigers, looking and feeling rejuvenated.
During his second Minor League stay this season, Herrera pitched a total of 13 1/3 innings for Triple-A Omaha and Double-A Northwest Arkansas, giving up just three hits and two runs with three walks, two hit batters and 21 strikeouts. Both runs came in the first of his seven outings.
"I feel great, I feel ready to go, ready to help this team," he said.
Herrera said he mixed in more breaking balls and changeups with his fastball, which often clocks 100 mph. He also worked on finishing off his pitches which enabled him to keep the ball down.
"It helped my command -- not a lot of walks," Herrera said.
The Royals wasted no time getting Herrera back into action. He relieved Ervin Santana in the eighth inning and retired both batters he faced in a 1-0 victory over the Tigers.
Kansas City celebrities play ball for charity
KANSAS CITY -- Before the Royals opened the second half against the Tigers on Friday night, a group of comedians and actors took the field at the Little K for the third annual Celebrity Wiffle Ball Classic.
Kansas City natives Jason Sudeikis, Rob Riggle and Paul Rudd visited Children's Mercy Hospital in Kansas City on Friday morning before arriving at Kauffman Stadium, where they took batting practice with the Royals and played in the Wiffle Ball Classic with about a dozen famous friends. They also came out to sing "Take Me Out to the Ballgame" during the seventh-inning stretch.
The group is in town for the fourth annual Big Slick Poker Tournament and Party at Harrah's North Kansas City Casino on Saturday to benefit the Cancer Center at Children's Mercy.
FOX Sports KC ratings on rise for Royals
KANSAS CITY -- The ratings for Royals games on FOX Sports Kansas City are up 43 percent this year, reflecting the biggest improvement in the Major Leagues according to Nielsen Media Research.
The Royals games on FOX Sports Kansas City are averaging a 5.8 household rating in the Kansas City designated market area and are on track to beat last year's 3.8 season average, which was the highest ever for Royals cable telecasts.
This season, Royals viewership ranks seventh in MLB local market TV ratings at the break after finishing 15th last year.
"There is a heightened level of excitement around and interest in Royals baseball, and that shows in the increased viewership," said FOX Sports Kansas City general manager and senior vice president Jack Donovan.
The top five highest-rated Royals games on FOX Sports Kansas City have all been this season and the most popular game was June 11 against Detroit -- a 3-2 Royals loss -- which averaged an 8.8 rating and peaked at 11.2 (104,000 households). With 16 night games in June, FOX Sports Kansas City ranked No. 1 on 11 of those nights and beat the NBA and NHL Finals.
Dick Kaegel is a reporter for MLB.com. Teddy Cahill is a reporter for MLB.com. Follow him on Twitter at @tedcahill. Kathleen Gier is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.