AP Photo Milwaukee Brewers’ Christian Yelich is congratulated after hitting a grand slam during the fourth inning of Monday’s game against the Pittsburgh Pirates in Milwaukee.

MILWAUKEE — Christian Yelich belted a grand slam for his first homer of the season and the Milwaukee Brewers beat the Pittsburgh Pirates 6-1 on Monday night.

Yelich’s two-out slam capped a five-run rally off Pirates starter Zach Thompson (0-1) in the fourth inning. The 429-foot blast was Yelich’s fourth career grand slam.

It was an encouraging sign for the 2018 NL MVP, who has struggled the last two seasons after leading the league in batting average, slugging percentage and OPS during each of his first two years in Milwaukee.

Yelich batted .248 and homered nine times in 475 plate appearances last year after hitting .205 in the pandemic-shortened 2020 season.

Eric Lauer (1-0) gave up one run and five hits in six innings while striking out five and walking one. Pittsburgh got its only run in the fourth on rookie Diego Castillo’s first career homer, which came one pitch after Castillo swung at a slider from Lauer that hit him in the knee.

Milwaukee’s Jandel Gustave, Hoby Milner and Jose Urena each pitched one inning of scoreless relief.

The game was tied 1-1 when Milwaukee’s Omar Narvaez singled to center and Lorenzo Cain hit a deep fly that appeared to bounce off the glove of right fielder Cole Tucker for a double.

Kolten Wong’s sacrifice fly brought home Narvaez with the go-ahead run. After Willy Adames walked, Yelich sent an 86 mph changeup into the second deck of the right-field stands.

Yelich finished 2-for-3 with a third-inning double and a walk.

The Brewers opened the scoring in the first when Wong hit a leadoff single, advanced to third on Adames’ single and came home on a wild pitch.

Thompson struck out five but allowed six runs, six hits and four walks in four innings.

HAINES’ RETURN

Pirates hitting coach Andy Haines, who had the same job with the Brewers from 2019-21, was back in Milwaukee for the first time since the Brewers fired him.

Milwaukee scored six runs during its four-game NL Division Series loss to the Atlanta Braves. The team then became one of 17 in the majors to change hitting coaches.

“It’s a lot to process because you’re so invested,” Haines said before the game. “I just know how much of a responsibility I felt to the players, to the organization. To all of a sudden not be a part of it, there’s emotions that you have to process.”

Haines said he was surprised by the decision but still respects Brewers president of baseball operations David Stearns and manager Craig Counsell.

“I also told them I accept it,” Haines said. “I don’t agree with it. I’m not going to concede that. I wouldn’t have a chance to be good at this job if I did, to be honest. That’s the reality of it, too. It doesn’t change how much I respect them. It actually probably would have made it easier if I didn’t respect them so much, their decision-making ability, to be honest.”

TRAINER’S ROOM

Pirates RHP Luis Oviedo (sprained right ankle) was reinstated from the injured list and optioned to Double-A Altoona after completing his rehabilitation assignment.

UP NEXT

JT Brubaker (0-1, 9.82 ERA) starts for the Pirates and Corbin Burnes (0-0, 2.25) pitches for the Brewers as this three-game series continues tonight.