CINCINNATI -- — Lane Thomas hit a grand slam in the first inning and Luinder Avila pitched a career-high five innings as the Kansas City Royals snapped a six-game skid with a 9-2 win over the Cincinnati Reds on Monday night. Kansas City (23-37) won for just the fourth time in 20 games. Avila (1-2) made his second career start and allowed one run on two hits with four walks and a career-high five strikeouts on 86 pitches, also a career high. Avila is replacing left-hander Kris Bubic, who is sidelined with arm issues. Jac Caglianone hit a two-run home run, his sixth of the season, in the fifth and Michael Massey added a solo homer in the seventh, both off Reds lefty Brandon Leibrandt. Leibrandt gave the Reds' injury-riddled bullpen a boost by pitching six innings, allowing five earned runs on 10 hits. Reds right-hander Lyon Richardson (0-1) made his fifth career start after Chase Burns, who has a 1.96 ERA in 11 starts, was scratched due to illness. Richardson lasted one inning, issuing two walks and hitting a batter before allowing Thomas' third career grand slam that gave the Royals a 4-0 lead. It was Thomas' second home run of the season and first since April 26. He went 3 for 5 with a homer, double, and four RBI. Reds left fielder JJ Bleday hit a solo home run, his 10th of the season and third in four games, in the first inning to make the score 4-1. It was just the second homer allowed by Avila this season through 36 innings. Highly rated infield prospect Edwin Arroyo made his major-league debut at second base for Cincinnati and singled in the ninth inning for his first career hit. He went 1 for 4 and made one fine defensive play. The 22-yeare-old was recalled from Triple-A earlier Monday when Elly De La Cruz was placed on the 10-day injured list with a right hamstring strain. Up next Royals LHP Noah Cameron (2-4, 4.61) will oppose Reds LHP Andrew Abbott (4-3, 3.88) on Tuesday night.