Alex Bregman and Kyle Tucker also contributed with solo home runs for the Astros, who are headed to the playoffs for the eighth consecutive year.

The Astros were down by one run with no outs in the fifth inning when Victor Caratini got a single and moved to second after a sacrifice bunt by Jeremy Peña.

Heyward, who had already dazzled defensively earlier in the inning, hit his home run deep into the right field stands off pitcher Logan Gilbert (8-12), putting Houston ahead 4-3.

Heyward joined the Astros last month after being released by the Dodgers and is stepping in for Yordan Alvarez, who is sidelined with a knee injury.

“What an opportunity,” Heyward said. “You never know where you’re going to be. It’s a different journey than most to get here, but it’s really cool that the game allows that to happen.

And to come into a winning clubhouse, with a winning culture, that says a lot about what people think of me and it’s fun to give that back to them.”

In the eighth inning, the Mariners had runners on first and third with one out, but Ryan Pressly retired Mitch Garver on a flyout. Josh Hader then came in and struck out J.P. Crawford to maintain the lead.

Hader returned for the ninth inning, getting pinch-hitter Luis Urías out before striking out Victor Robles and Julio Rodríguez to secure his 34th save.

Astros manager Joe Espada was emotional when the final out was made.

“Oh my God. Unbelievable,” he said. “Tears came out of my eyes. I’m emotional because I care about this team. I love this team, and the fact that we are in a position to compete for another World Series is special.”

Framber Valdez (15-7) gave up eight hits and three runs in 5 2/3 innings to earn the win.

For the Mariners, Jorge Polanco hit a home run and had a season-high four hits, along with two RBIs. The Mariners fell 2 1/2 games behind in the race for the last two American League wild cards.

“It’s always hard when you watch a team celebrate,” Seattle manager Dan Wilson said. “But I think the message here is that there are many different scenarios that could still happen. We keep fighting … and we’ll see what happens.”

In the sixth inning, Justin Turner and Polanco got singles to start, but Garver grounded out, and Valdez struck out Crawford, ending his game.

Bryan Abreu came in to pitch, and pinch-hitter Luke Raley grounded out, allowing Houston to escape the situation.

Gilbert gave up five hits, four runs, and matched his season high by allowing three home runs in six innings.

With two outs in the first inning, Bregman hit a fastball from Gilbert over the center field fence, putting Houston ahead 1-0.

Polanco tied the game with a homer to left field on Valdez’s second pitch of the second inning.

Rodríguez and Cal Raleigh both got singles to start the third inning, and the Mariners took a 2-1 lead with an RBI double from Randy Arozarena. With one out, Polanco singled to score Rodríguez, making it 3-1.

Tucker hit a home run to start the fourth for Houston, bringing the score to 3-2.

In the fifth inning, Heyward made a spectacular catch in left field, leaping to rob Raleigh of a hit. He crashed into the metal scoreboard on the wall and knocked out a panel with his left hand.

Heyward was shaken by the impact and fell down in pain. An athletic trainer checked on him, but he stayed in the game and later hit his homer in the bottom half of the inning.

An avid football fan (A red). And an Otaku by the definition of the word.