Pittsburgh Pirates players celebrate a three-run walkoff home run in the ninth inning by Yoshi Tsutsugo Sunday at PNC Park. The blast gave the Pirates a 4-3 victory over St. Louis.

PITTSBURGH — Yoshi Tsutsugo hit a three-run homer off Alex Reyes in the ninth inning, sending the Pittsburgh Pirates to a 4-3 victory over the St. Louis Cardinals on Sunday.

Bryan Reynolds started the game-ending rally with a leadoff walk. After Colin Moran struck out swinging, Jacob Stallings walked and Tsutsugo drove Reyes’ next pitch deep to right.

“I was really only thinking about hitting a hard ball,” said Tsutsugo, who has homered five times on nine hits since signing with the Pirates on Aug. 16. “It’s really comfortable for me. The manager, the staff, my teammates. We joke around a lot and make it a really nice environment for me. It was really easy for me to transition in this team.”

Reyes (5-7) has allowed at least one run in four of his last six appearances.

Chris Stratton (5-0) got the win, striking out the side in the top half of the inning. Stratton and fellow relievers Chad Kuhl and David Bednar combined to allow one hit over four innings.

“Our bullpen was outstanding, really kept us in the game,” manager Derek Shelton said. “Our guys don’t give up. To win that game today and come back against a team like that, that’s big steps for us. Those are important.”

Pittsburgh earned a split of the four-game series, bouncing back from a 13-0 loss Saturday.

St. Louis remains 3 1/2 games back of Cincinnati for the second NL wild card. The Reds lost 2-1 to the Miami Marlins on Sunday.

“It hurts like crazy,” Cardinals manager Mike Shildt said. “It hurts everybody that’s invested in our team. It hurts our team. It’s tough. We’re fighting our tails off. We don’t have a lot of margin for error is probably a big part of this. We do all these little things right, but we don’t create a lot of margin for error.”

The game was tied at 1 before Tommy Edman hit a two-run homer for St. Louis in the fifth, sending a 418-foot drive into the seats in right-center. Edman’s ninth homer of the season gave him nine RBIs in his past four games.

Edman also doubled and scored on Tyler O’Neill’s first major league triple in the third.

The Pirates opened the fourth with three consecutive singles, and Tsutsugo got his team on the board with a sacrifice fly.