HOUSTON -- Within a span of five pitches in the top of the ninth inning Saturday, the Red Sox rallied to tie the Astros by scoring twice against lockdown closer Roberto Osuna. It was Osuna’s first blown save as a member of the Astros, but his teammates made sure it didn’t ruin the night.

Carlos Correa stroked a bases-loaded, RBI single to right field off Matt Barnes in the ninth inning to score Aledmys Diaz from third base with the winning run and send the Astros to a 4-3, walk-off victory over the Red Sox at Minute Maid Park.

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“He did a magnificent job keeping the game tight,” Correa said of Osuna. “That was huge for us to win this game and celebrate.”

The Astros, who have won 17 of their last 21 games, will send Justin Verlander to the mound Sunday afternoon to try to sweep the defending champs. Houston has already won the season series, taking two of three from the Red Sox in Boston last weekend and winning the first two games of the series in Houston.

The Astros rallied to win after Osuna’s streak of 25 consecutive converted save chances was snapped in the top of the ninth.

Osuna squandered a 3-1 lead after throwing only five pitches to begin the inning, with Boston tying the game on a two-run single by Christian Vazquez. He came back to strike out Steve Pearce and get Andrew Benintendi to pop out. After walking Mookie Betts, he ended the threat by retiring Mitch Moreland with the bases loaded.

“This was one of those days,” Osuna said. “They attacked me early, but I was able to make the adjustments late in the inning and keep the leading run at third. … I was able to keep the game close for the guys to win.”

Last Saturday at Fenway Park, Astros manager AJ Hinch brought Osuna into a game in which the Astros led by four runs because he said the Red Sox are never out of a game.

“You never feel comfortable when you're facing this team,” Hinch said. “Osuna’s been perfect early for us. I’m glad our team picked him up when there was a few bad pitches, a little bad luck. ... He did a sensational job getting out of that inning without any damage after they tied it up.”

For Osuna, it was his first blown save since the Red Sox scored a pair in the ninth inning on April 24, 2018, while he was a member of the Blue Jays.

“I remember when I was in Toronto in ‘17, I believe, and they scored four runs on me in the ninth inning, so I know how good this team is,” Osuna said.

Astros starter Brad Peacock threw six scoreless innings and lowered his ERA to 0.39 ERA in four starts since giving up seven runs in 3 2/3 innings at the Twins on May 2. In that span, he’s allowed 13 hits and one run and struck out 32 batters in 23 innings pitched.

This was the first game this season the Astros won without hitting a homer (1-8).

Stassi injures knee

Astros catcher Max Stassi left the game after the fourth inning with left knee discomfort when he ran out a ground ball. Stassi grounded out to short to end the fourth and put on his gear for the fifth, but he came out of the game after his knee hurt him when he squatted behind the plate. More will be known about Stassi’s prognosis on Sunday.