Houston pitchers Tatsuya Imai, Steven Okert and Alimber Santa combined for a no-hitter as the Astros beat the Texas Rangers 9-0 on Monday in Arlington, Texas.

Imai (2-2) walked four batters and struck out two over a career-high six innings. Okert worked around a leadoff walk in the seventh. Santa pitched two perfect innings in his major league debut to close out the Astros' 18th no-hitter and fifth combined no-hitter in franchise history.

In the ninth, Joc Pederson lined out softly to second base, Alejandro Osuna grounded out to third, and Brandon Nimmo struck out looking to end it. Nimmo challenged the called third strike, but a video review confirmed the ruling.

Asked his reaction to being involved in a no-hitter to open his career, Santa said, "I was a little surprised. Yordan (Alvarez) told me, 'Santa, do you know what you just did?' I know it's something historic."

Santa added, "Everything was under control in the bullpen (before entering). I just felt some adrenaline, but I tried to tell myself to calm down and remember to do what I've been doing ever since the minor leagues. ... I was aware of the no-hitter, but I was just trying to calm myself down from the bullpen."

Houston recorded the majors' first no-hitter since three Chicago Cubs pitchers blanked the Pittsburgh Pirates in a 2-0 win on Sept. 4, 2024.

Christian Walker hit a three-run home run and Alvarez added a solo shot for Houston, which won its fourth straight game and has won seven of its last 10. Nick Allen had two hits and two RBIs, and Christian Vazquez added two hits and an RBI.

The Astros registered their first no-hitter since Ronel Blanco stopped the Toronto Blue Jays 10-0 on April 1, 2024. The Rangers were last no-hit by the New York Yankees' Corey Kluber in a 2-0 loss on May 19, 2021.

Texas has lost four straight to fall a season-high five games under .500.

Houston pushed a run across in the first inning against Kumar Rocker (2-5) when leadoff hitter Jeremy Pena was hit by a pitch, stole second base, moved to third on Isaac Paredes' groundout and scored on Alvarez's sacrifice fly.

In the bottom of the first, Imai walked the first two Texas batters, leading to pitching coach Josh Miller making a mound visit. Imai then induced a double-play grounder from Nimmo, walked one more batter, then closed the inning by inducing a flyout.

"In the first inning, I felt unbalanced," Imai said. "The timing was off. But after that inning, I was able to adjust the timing or the rhythm ... and that's why I was able to perform well."

Astros catcher Christian Vazquez said, "After that first inning, he looked calm and (threw) a lot of strikes and they were chasing a lot of the sliders, so it was amazing."

Alvarez -- who exited the Saturday game with a back spasm and sat out a game for the first time this season on Sunday -- put the Astros ahead 2-0 with a leadoff homer in the fourth inning.

The 415-foot blast over the right-center field wall was Alvarez's team-high 16th homer of the season.

Houston added to its lead with two runs in the fifth. Zach Dezenzo drew a leadoff walk, advanced to third on Allen's single and slid home ahead of the tag on Vazquez's bunt to the pitcher. Pena followed with a single to right field to score Allen from second base.

Rocker allowed four runs on four hits over five innings. He walked two and struck out five.

The Astros broke the game open with five runs in the seventh inning against Peyton Gray. Walker hit a three-run shot with two outs, his 15th homer of the season and fourth in the past three games. Allen added a two-run single to increase Houston's cushion.