OAKLAND -- Frankie Montas embraced the first Opening Day assignment of his career this season as an opportunity to prove that he can be a No. 1 pitcher in this league. Four starts in, he’s looked every bit of the ace the A’s were hoping for.

The A’s rode another strong outing from Montas, who combined with Jake Diekman and Liam Hendriks for a 3-1 victory over the Astros on Saturday at the Coliseum. The win pushed Oakland’s Major League-best winning streak to eight games and gave the club a 4 1/2-game lead in the American League West.

Montas was dominant, limiting Houston to just two hits over seven scoreless innings. He appeared to be getting stronger as the game went along, striking out five and retiring the final nine batters he faced.

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“He had really good command of everything today and looked in control. Good split and good slider,” A’s manager Bob Melvin said. “There’s a reason we pitched him on Opening Day. I’m sure when teams look at the matchups against us, they don’t particularly look forward to him.”

Montas produced 10 swings and three whiffs on the 19 sliders he threw Saturday afternoon. He also went to the slider as the putaway pitch on two of his strikeouts.

The right-handed-heavy Astros lineup played right into Montas’ strengths. Through his first four starts, right-handers are now 3-for-37 against Montas after Houston’s righties combined to go 2-for-15 against him.

“The guy was dealing. He was getting ahead of hitters with low and away first. If you swing at it, it wasn’t a good pitch to hit, and if you took it, it’s a strike,” Astros manager Dusty Baker said. “He’s very relaxed. I had never seen this guy in person, but he was tough. He stayed about 96, 97 mph damn near the whole day with a slider, good breaker.”

The pre-2019 version of Montas might have been flustered entering a start against such a potent offense. But after his dominant first half of ‘19, the right-hander has gained a newfound confidence. He brings a certain swagger to the mound that feels unhittable. And he nearly was on Saturday, as Yuli Gurriel was responsible for Houston’s only two hits against Montas.

“He’s gotten to the point now where he doesn’t really care who he faces, he just likes pitching,” Melvin said. “Last year, he really came into his own. He came into this season really looking forward to leading the way. He’s feeling it at this point. That all comes with maturity and his multiple pitches.”

On a day when he tied an Oakland record that belonged to Rickey Henderson by starting his 148th consecutive game in the leadoff spot, Marcus Semien did his best impression of the Hall of Famer in the first as he blasted a leadoff homer off Framber Valdez.

The homer may have been a carryover effect from the night before, when Semien ended a 13-inning thriller against Houston with a walk-off single. According to the Elias Sports Bureau, Semien was the first A’s player since 1901 to lead off a game with a home run after ending the previous game with a walk-off RBI.

“We’ve been starting slow in the first inning,” Semien said. “As a leadoff hitter, you’ve got to do what you can to get on base and score runs. Leading off a game with a home run is the best thing you can do.”

Oakland’s second run of the day was also a result of Semien’s hustle. After a leadoff single in the sixth, Semien swiped second base and raced over to third on a bad throw that sailed into the outfield from Astros catcher Dustin Garneau. Two batters later, Semien scored on a groundout by Matt Chapman.

“That’s why he was third in MVP voting last year,” Melvin said of Semien. “He leads off. He’s durable. He’s a team leader. He can run. Terrific fielder now. He can do it all. There are times when guys like that show up in multiple facets during the course of a game. It’s really fun to watch.”

Chapman muscled a solo shot into the right-field bleachers in the eighth to provide an insurance run for Hendriks, who recorded his fifth save of the year.

With a record of 11-4, the A’s matched their best record through the first 15 games of a season (2014) over the past 30 years. They reached the postseason as a Wild Card team that year. Saturday’s win also has the A’s in position for a three-game sweep, feeling good about their chances with No. 1 prospect Jesús Luzardo set to take the mound in Sunday’s series finale.

“[The Astros] are the team we’re always battling for the top spot,” Montas said. “To take these first two games is huge. This puts us in a good spot.”

Up next
Luzardo takes the mound for the A's in Sunday's three-game series finale against the Astros at the Coliseum at 1:10 p.m. PT. He will be making his second Major League start, looking to carry over the success from the first, which saw him toss five scoreless innings against Texas. Right-hander Cristian Javier will start for Houston. Fans can watch the game on NBC Sports California and MLB.TV or listen on A's Cast.