KANSAS CITY, Mo. -- Eric Hosmer hit a three-run homer with two outs in the ninth inning off former Kansas City teammate Greg Holland, lifting the Royals over the Colorado Rockies 6-4 on Wednesday night.
Hosmer's 21st home run of the season was the first game-ending shot of his career.
Holland (2-5) fell to 0-4 with one save in four opportunities in his past six games, allowing 10 hits, three home runs and 12 runs over five innings. The former Royals closer issued a leadoff walk in the ninth, gave up a two-out single to Melky Cabrera and then was tagged by Hosmer on a 1-1 pitch.
Brandon Maurer (2-1) pitched the ninth.
Charlie Blackmon and Nolan Arenado homered for the Rockies in a matchup of playoff contenders.
Blackmon hit his career-high 30th. He became the first National League leadoff man to reach 30 home runs since Hanley Ramirez of the Marlins in 2008.
Arenado, who has homered in back-to-back games, hit his 29th in the first. He leads the majors with 108 RBI and 74 extra-base hits.
Arenado has a major league leading .430 batting average in the first inning.
Rockies rookie Antonio Senzatela allowed nine hits but just two runs in five innings.
Ian Kennedy failed to make it out of the fifth for Kansas City, yielding three runs on seven hits, including two home runs. In his past two starts, he has surrendered eight runs on 13 hits, including four home runs, in 7 1/3 innings.
Kennedy is 0-6 with a 5.97 ERA in 12 home starts this season. He has a franchise record of 16 winless starts since beating the Minnesota Twins on Aug. 20, 2016.
Whit Merrifield had four hits for the Royals, matching his career high.
Rockies: IF-OF Ian Desmond (right calf strain) will begin a rehab assignment Thursday with Triple-A Albuquerque. If he has no setbacks, Desmond could be activated Sunday. . LHP Tyler Anderson (left knee inflammation) threw a 45-to-50 pitch three inning simulated game. He will throw another simulated game before going out on a rehab assignment. "This is more about, I think, the knee strength moving forward," Rockies manager Bud Black said. "His arm has felt pretty good all year.
Royals: RHP Kelvin Herrera will circumvent a trip to the disabled list after being removed in the ninth inning Tuesday with forearm tightness. The Royals do not expect their closer will miss much time, if any.
Rockies: RHP German Marquez is 2-0 with a 2.00 ERA in three starts against American League clubs.
Royals: RHP Jake Junis has a 4.79 ERA in his eight major league starts.