OAKLAND -- Frankie Montas reached the Major Leagues because of his blazing fastball. His splitter might be what keeps him here for a long time.

“There was a point in his career where he was on the path to do this,” A’s manager Bob Melvin said. “The injury sidelined him a little bit and he ended up being a reliever. He got humbled a little in relief and had to find a different way to do it. We’ve seen it all spring and now in the regular season.”

The right-hander can light up the radar gun with the best of them, and he often overpowered the Houston Astros in Wednesday’s 2-1 win with a fastball that touched up to 99 mph. But his new and improved splitter was what afforded him the opportunity to keep his pitch count low as he cooled off the defending American League West champions, who were riding a 10-game winning streak.

“It’s been the key. It’s a true third pitch,” Melvin said of the splitter. “The slider was pretty good, too. A mix of pitches like that, throwing strikes and getting ahead, he’s a tough guy to hit when he’s ahead in the count and feeling pretty good.”

Montas held the Astros hitless through the first four innings, allowing just three hits over 6 1/3 innings. He kept his pitch count at an economical 88 by showing an ability to get ahead in the count and produce quick outs throughout the night.

It was an improvement from his start earlier this month at Minute Maid Park, where he still pitched well but ended up taking the loss despite allowing only two earned runs over five innings.

That night, Montas said falling behind in the count was his downfall. On Wednesday, he placed an emphasis on getting ahead of batters, and the results showed.

Of the 25 batters he faced, Montas went to a full count just four times. He induced a first-pitch out on three occasions and did not allow his two walks until the sixth.

“He’s really good,” Astros manager AJ Hinch said. “We got to him a little bit last time, but he’s got really good stuff. He really didn’t concede much of anything. His power, his fastball was good, his breaking ball was good, he threw a split -- his stuff was overpowering tonight.”

When Montas did get deeper in counts, he finished off hitters with the splitter in five of his six strikeouts. Perhaps the most impressive of the night came against Jose Altuve in the sixth.

After walking George Springer with one out as he appeared to lose control of his fastball, Montas turned to his offspeed stuff. He threw nothing but offspeed pitches to Altuve in the at-bat, with the fifth pitch a nasty splitter down in the zone that got Altuve to swing through for strike three.

“He’s a really good hitter,” Montas said of Altuve. “But I feel like when you pitch him in and out and hit your spots, he’s going to swing. He’s always swinging, always hacking, and I threw the perfect pitch at the right time.”

Matt Chapman made sure Montas’ impressive night was rewarded with a win. After Montas surrendered a game-tying two-out single to Michael Brantley in the top of the sixth, Chapman led off the bottom half by unloading on a 1-1 cutter from Wade Miley for his sixth home run of the year.

The majestic homer was blasted into the left-field bleachers and traveled 441 feet with an exit velocity of 111.5 mph, both season-highs for an A’s home run, according to Statcast.

Chapman entered the night 1-for-6 in his career against Miley, and he was not the only A’s hitter who has had trouble with the left-hander. Miley entered the night 5-1 with a 1.40 ERA in six career starts against Oakland, so the A’s were glad to just make any type of dent in Miley’s pitching line.

“Miley kind of owned us a little bit,” Chapman said. “We weren’t able to put that much runs up, so it was nice to find a way to win that game.”

Pitching on four days of rest, Lou Trivino entered the game in relief of Montas with one on and one out in the seventh and was flawless. The flamethrowing right-hander struck out three batters over a perfect 1 2/3 innings. He now leads all Major League relievers with 19 strikeouts.

“I’ve talked to some of the guys on other teams that have been on base and asked them what facing Trivino is like, none of them say it’s a fun at-bat,” Chapman said. “He’s got four power pitches and that curveball to keep guys off balance is nasty. You don’t see too many guys take good swings off Lou. I’m just happy he’s on our team.”

Blake Treinen found himself in a ninth-inning jam after allowing two of his first three batters faced to reach base, but he shut the door with a strikeout of Robinson Chirinos to record his sixth save of the year. The scoreless ninth pushed his streak of consecutive scoreless frames at home to 26 going back to 2018, the longest streak by an A’s reliever since Dennis Eckersley’s 26 1/3 from June 6-Aug. 2, 1987.

After the A’s were blown out by Houston the night before, Chapman said the club’s ability to bounce back with their first win of the year against the Astros showed what they are made of.

“Coming off the game yesterday, it stuck with us a little bit,” Chapman said. “Our team is tough and we are able to move past tough games. That’s a good quality of a winning team.”