HOUSTON -- If the Astros are going to turn their season around, they know they have to start hitting better. Their record in low-scoring, close games has been subpar, and if they expect to make a push in an unspectacular (and still very winnable) American League West, they’ll have to get more from what has been mostly a sputtering offense of late.

Monday night proved to be a good place to start, with several hitters who have been navigating through multiple frustrations at the plate proving to be the heroes in the Astros’ 7-4 win over the Cardinals at Minute Maid Park.

But while this was a multi-player effort, there was one Astro who needed a big night perhaps more than the others: catcher Yainer Diaz, whose two-run homer in Houston’s four-run eighth put the club ahead of St. Louis for the first time all night.

“That could turn things around quickly,” manager Joe Espada said. “It was a big homer.”

And it capped an inning reminiscent of a better time for the Astros, when runs more often came in bunches.

With Houston trailing 4-3 in the eighth inning, Alex Bregman, who struck out looking in his prior two at-bats, unloaded on a JoJo Romero changeup, sending it a Statcast-projected 414 feet to left field to tie the game at 4. Jake Meyers followed with a base hit, and Jeremy Peña pushed a bunt to the right side of the infield to advance Meyers to second.

Pinch-hitter José Abreu struck out, but Diaz, who had not homered since April 11, launched a 393-foot shot into the left-field Crawford Boxes, giving the Astros a two-run lead. The homer ended Diaz’s homerless streak at 148 at-bats.

“You guys can imagine how that must have felt -- it’s been a while,” Diaz said. “I’ve been battling, going through a couple things. That’s [what] happens, the results you get, when you don’t give up.”

“It was a well-executed changeup that he went and got and kept it fair,” Espada said. “That stuff right there gets you going. It was a big, big swing, and we needed that.”

Diaz’s emotions bubbled up as he watched the ball clear the left-field wall. He put his right arm in the air, pointed upward and slapped his bat as he started his quick trot around the bases.

“It was one of those things where it almost felt like a weight was lifted, to an extent,” Diaz said, through interpreter Jenloy Herrera. “Baseball is one of those sports that’s a lot about confidence, and when you’re going through the stretch I was going through, some of that confidence goes away. When I hit that home run, it definitely felt good there.”

Diaz is carrying a heavy load this season, his first as the Astros’ frontline catcher for a rotation that is -- when healthy -- filled with veteran pitchers. Diaz has struggled to settle in offensively; in May, he batted .200 (17-for-85) with a dismal .213 on-base percentage.

The prolonged slump has created an opening for Victor Caratini to get more playing time behind the plate.

Monday’s breakout was more in line with what the Astros have been expecting from their 25-year-old catcher.

“That's what he's capable of,” Bregman said. “He's an unbelievable hitter. For him to do that right there for us was huge.

“He's busting his butt every single day trying to catch a winner and also put good swings on the ball. So I'm really proud of him.”

The Astros have more work to do. Entering the series with the Cardinals, they were 5-13 in one-run games and 3-6 in two-run games. They had lost five of their past seven games.

“Hopefully that’ll be a catalyst moving forward,” said Justin Verlander, Monday’s starting pitcher, of the breakout win. “I know that we’ve struggled late in games, in one-run games, in tie games, blah blah blah. [The win] was nice. Sometimes you just need the dam to break, and hopefully this was that.”