PHILADELPHIA -- A's right-hander Daniel Mengden's quirky windup kept the Phillies' bats off balance and silent Friday night at Citizens Bank Park.

Mengden enjoyed the best start of his 18-start career, pitching his first career shutout in a 4-0 victory. It is the A's first shutout since Aug. 19, 2016, when Kendall Graveman tossed a two-hitter against the White Sox in Chicago. Mengden allowed just two hits and struck out seven, largely in part because he alters his time to the plate from the windup to mess with the hitter's timing. Certain attributes of the Phillies hitters made this exponentially more effective.

"A bunch of the Phillies hitters have a [leg kick] and like to time it off the pitcher," Mengden explained. "I was waiting on [catcher] Bruce Maxwell to tell me when to do it, and I trust him a lot and we had a plan going in, throwing backwards a lot, mixing it up a lot, and just kind of being as unpredictable as possible with the normal pumps and the quick pitches."

"As the game went along you could see his confidence grow and grow," A's manager Bob Melvin said. "We don't see a whole lot of [complete games] anymore, so he deserved a chance to go out there for the ninth. He wasn't going to get much rope, but you could just see his confidence grow as the game went along."

Oakland has won seven of its last nine games.

The Phillies never threatened as they snapped their three-game winning streak. J.P. Crawford singled in the third and the sixth. Aaron Altherr flied out to the warning track in left field in the seventh. Rhys Hoskins, who had homered six times in the previous six games, went 0-for-3 with two strikeouts.

"Obviously, he pitched awesome tonight," Phillies catcher Andrew Knapp said about Mengden. "It's a funky delivery, a funky windup. He kind of messes with your timing with the double pump over the top. Kudos to him. He was hitting his spots and keeping us off balance."

The Phillies had been swinging the bats well, too. They had averaged 6.5 runs per game in their previous 12 games.

"I'm glad I didn't give J.P. Crawford the night off," Phillies manager Pete Mackanin said.

• Klentak commends Mackanin's job in rebuild

MOMENTS THAT MATTERED

Olson crushes one: Phillies right-hander Mark Leiter walked Jed Lowrie with two outs in the first inning, then Matt Olson hit a 2-2 fastball into the second deck in right field for a two-run homer, handing the A's a 2-0 lead. The ball left his bat at 109.4 mph, according to Statcast™. It was Olson's 19th homer of the season. More >

Two-out troubles continue: Leiter retired the first two batters he faced in the second, but much like the first, he couldn't finish the inning. He allowed a two-out single to Mengden. Matt Joyce followed and ripped a first-pitch changeup into the right-field stands for a two-run homer to make it 4-0. It was his 24th homer of the season.

"Take two pitches away and we're still playing, maybe," Knapp said of the two two-out homers.

"It was just two big blows that gave us some cushion and gave us some breathing room," Melvin said.

QUOTABLE

"The two homers put us in a tough hole, which is disappointing. But after that I tried to keep us in it as long as I could." -- Leiter, on his performance against the A's

SOUND SMART WITH YOUR FRIENDS

Leiter allowed seven hits, four runs, one walk and struck out a career-high nine in six innings. According to Elias Sports Bureau, Leiter is the first Phils pitcher with nine or more strikeouts in both a start and a relief appearance in the same season since Gene Conley in 1959. Leiter pitched 4 1/3 innings in relief at Colorado on Aug. 5 and struck out nine.

INSTANT REPLAY

The Phillies won a challenge in the fifth inning. A's second baseman Jed Lowrie doubled to left-center field, but the Phillies thought Cesar Hernandez applied the tag before Lowrie reached safely. Replay confirmed he did, and the call was overturned.

WHAT'S NEXT

A's: Oakland sends Kendall Graveman (5-4) to the bump Saturday to face the Phillies for the first time. He holds a 4.48 ERA on the year, but a 3.92 ERA since Aug. 8. First pitch is at 4:05 p.m. PT.

Phillies: Phillies right-hander Ben Lively (3-6, 3.86 ERA) pitches the second game of the series starting at 7:05 p.m. ET. Perhaps nobody other than Aaron Nola is a lock to make next season's rotation, but Lively has pitched well enough in 12 starts to be considered a frontrunner to other pitchers in the organization.

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