ST. LOUIS (AP) — Michael Chavis has figured out the key to success with the bases loaded.

Chavis hit a go-ahead grand slam as the Pittsburgh Pirates overcame a three-run, third-inning deficit, and beat the St. Louis Cardinals 9-4 on Sunday for their first win this season.

Chavis made his first start of the season and homered off left-hander Steven Matz (0-1), who allowed seven runs and nine hits over three innings in his first start since signing a $44 million, four-year contract.

It was the second slam of Chavis’ big league career in 14 at-bats with the bases full. He finished a triple shy of the cycle.

“Any time the bases are loaded, you know the pressure is on the pitcher,”: Chavis said. “I’m huge on mental skills. I kind of change the perception from I need to produce to the pressure is on him and he has to produce. He has to make and execute pitches in order to get me out.”

Chavis drove the first offering over the wall in left.

“It got us on the board and showed that even though we lost the first two games, we’re going to continue to go,” Pittsburgh manager Derek Shelton said. “It us started.”

Chavis was just as pleased with his play at first base. Twice, he had to do the splits to grab a throw from his infielders.

“When I do it, I’m really proud about it,” Chavis said. “It’s something I’ve had to work for. When I was growing up I was not a super-flexible person.”

Diego Castillo added three hits for the Pirates, a day after the 24-year-old got his first hit in his second big league game.

Nolan Arenado hit a two-run homer in the first for St. Louis, which played its second straight game managed by bench coach Skip Schumaker, in charge while manager Oliver Marmol has the flu. Arenado has two homers and seven RBIs in three games.

Ke’Bryan Hayes, Kevin Newman and Jake Marisnick also had RBIs for the Pirates, who scored eight unanswered runs after falling behind 3-0 in the first.

Roberto Perez, Hayes and Bryan Reynolds singled in the third before Chavis’ home run.

Miguel Yajure (1-0) pitched two scoreless innings. It was his first major league win in his eighth appearance. Yajure’s teammates doused him with water in the clubhouse after the contest.

“It was good, everybody was yelling at me and saying congratulations,” Yajure said. “I’ve worked really hard and it’s good to finally get it.”

Bryse Wilson surrendered three runs in the opening inning before tossing three scoreless innings.

“Three runs, we can overcome that,” Wilson said. “The main goal was to keep the team in the game.”

Matz allowed just one hit over the first two innings before imploding in the third.

“You want to go deep in games, it was really frustrating,” Matz said. “Especially when you come out hot and get three runs. Right off the bat, you want to get the guys back (in the dugout) as quick and possible and I wasn’t able to do that.”

UPON FURTHER REVIEW

The Cardinals won their challenge in the seventh inning when Tommy Edman was initially ruled out by first base umpire Dan Merzel after a grounder to shortstop. After a video review, crew chief Jim Reynolds announced the call had been overturned.

WELCOME TO THE BIGS

St. Louis RHP Andre Pallante pitched the seventh inning his big league debut and allowed two hits, including a run-scoring hit to Jake Marisnick. The Cal Irvine product was a fourth-round pick in the 2019 amateur draft.

EARLY MAGIC

The Cardinals have scored in the first inning in each of the first three games for the first time since Apri 7-10, 1977.

UP NEXT

Pittsburgh RHP Zach Thompson (3-7, 3.24 last season) will face RHP Dakota Hudson (1-0, 2.08 ERA) in the final game of the four-game series on Monday afternoon. Thompson was acquired from Miami on Nov. 29. Hudson is 2-1 with a 3.90 ERA in nine appearances against the Pirates.

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