CINCINNATI -- Patrick Corbin throws his slider more than any other pitch. He produced more strikeouts off the slider last season than any other Major League pitcher. But on Friday night, Reds batters weren’t biting. They laid off Corbin’s slider, forced him to pitch to their strengths, and the result was a rare poor outing for the Nationals’ left-hander.

Corbin allowed eight runs (six earned) and 11 hits in a 9-3 loss to the Reds at Great American Ball Park. And as he said afterwards, “It happened quick.”

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Coming off a shutout in his last start, Corbin lasted only 2 2/3 innings on Friday, his shortest outing since he pitched in relief in 2017 while with the D-backs.

The first eight Reds batters reached base against Corbin in the first, and five of them scored. He allowed five runs on seven hits including a three-run home run by Curt Casali in the inning.

"That was a great start to the game against a really tough pitcher,” said Reds manager David Bell. “We really came out aggressive. We got a lot of first-pitch hits and were attacking early. Any time you get a chance to do that off a good pitcher, it says a lot."

Corbin’s 11 hits allowed tied a career high. The eight runs allowed were his most since 2013, although two of the runs on Friday were unearned.

Nationals manager Dave Martinez credited the Reds for their approach against Corbin, who is not the first pitcher they’ve pounced on in the first inning this season. Cincinnati has scored 47 runs in the first, the most they’ve scored in any inning.

“They laid off the slider, which he usually gets a lot of people to swing at,” Martinez said. “They had a good approach against him. They tried to stay up the middle. Didn’t try to do too much. He threw some sliders and they weren’t chasing, and he had to come back and throw strikes.

Corbin hasn’t fared too well against Cincinnati in his career, posting a 4.85 ERA against the Reds, highest of any team he has faced at least 10 times. Great American Ball Park is no picnic for opposing pitchers.

Despite throwing 116 pitches in his last outing -- a 5-0 win over the Marlins -- and 75 1/3 innings over 12 starts, Corbin said fatigue was not an issue on Friday night.

“We looked at that,” Martinez said. “He said he felt really good. Even when I took him out, he said, 'You know, I felt really good.' It’s just one of those days for him. He’s a professional. He knows what he’s going to give us next time out.

Juan Soto’s solo homer in the fourth, his 10th this season, was among the few offensive highlights for the Nats. He went 3-for-4 with a double.

The Nationals fanned seven times in the first three innings against Tyler Mahle, who struck out the side in the first and third frames. Mahle earned his first career victory over a National League East opponent.

The margin of defeat might have been larger had Nats center fielder Victor Robles not thrown out Nick Senzel trying to score in the fifth. It was the third outfield assist of the season for Robles.

“I felt good out there,” Corbin said. “They came out swinging and I didn’t execute as well as I have. I see teams trying to do that, stay away from that slider. I thought we had a good game plan.”

For the first time this season, Corbin pitched fewer than five innings. The last time he had an outing this short was on Sept. 29, 2017, vs. Kansas City when he pitched 2 2/3 innings in relief, giving up two hits and no runs.

For Corbin, it's probably just a blip on the radar. Martinez tipped his cap to the Reds.

“They’re swinging the bats really well, we knew that coming in,” Martinez said. “but we had Pat throwing tonight."