LOS ANGELES — Jose Altuve homered twice while reaching base five times and driving in five runs, and the Houston Astros routed the Los Angeles Dodgers 18-1 on Friday night in the series opener of a matchup between division leaders.

The defending World Series champion Dodgers were held to five hits and Will Smith’s solo homer in the team’s worst loss in Dodger Stadium history.

The AL West-leading Astros scored 10 runs in the sixth, highlighted by Victor Caratini’s grand slam and Altuve’s three-run shot. It was the most runs given up in an inning by the Dodgers since April 23, 1999, when they allowed 11 to St. Louis.

Houston’s Lance McCullers Jr. (2-3) allowed one run and four hits in six innings of his second start since returning from a sprained right foot. He struck out four.

Isaac Paredes hit his first career leadoff homer on the first pitch of the game from rookie Ben Casparius. Altuve doubled and scored on Walker’s RBI single for a 2-0 lead.

Jake Meyers doubled beading off the third and scored on Altuve’s 14th homer. Rookie Cam Smith doubled and scored on Walker’s 417-foot shot halfway up the left-field pavilion to cap four straight hits given up by Casparius and extend Houston’s lead to 6-1.

The Astros broke it open in the sixth. Smith had a bases-loaded RBI single, reliever Noah Davis hit Walker with two strikes to force in a run and Caratini hit his grand slam came with no outs. Meyers added an RBI single and Altuve hit his second homer of the night.

Caparius allowed six runs and nine hits in three innings and struck out three.

Dodgers fans relentlessly booed Altuve throughout his at-bats, chanting “Cheater! Cheater!” He’s one of two players, along with McCullers, remaining from Houston’s 2017 team that beat the Dodgers in the World Series. It later came out that the Astros were stealing signs with the help of video and relaying pitches to batters by banging on a trash can.

Key moment

Shohei Ohtani hit a 96-m.p.h. line drive off the left heel of McCullers in the third. The ball flew up and was caught by shortstop Mauricio Dubón, with the umpire signaling Ohtani out on the rare 1-6 putout.

Key stat

Cooper Hummel’s pinch-hit single in the fifth snapped a streak of 12 1/3 hitless innings by the Dodgers bullpen.

Up next

Astros LHP Framber Valdez (9-4, 2.72 ERA) starts Saturday. Dodgers RHP Shohei Ohtani (0-0, 2.25) will throw two innings as the opener on his 31st birthday.