CINCINNATI — Nick Pivetta looked toward left field on Friday night and flapped his arms wildly toward the ground, trying anything he could do to alter the flight of a fly ball and impede it from leaving Great American Ballpark.

The pitcher seemed to will the ball back to earth as it fell to the warning track and into the glove of Rhys Hoskins to end the third inning of a 6-4 loss to the Reds. But an inning later, there was nothing Pivetta could do to keep a three-run homer from soaring to right field. The pitcher didn't try flapping his arms this time as he failed to even turn and watch the ball that shot off Mason Williams' bat.

It was the second homer Pivetta allowed and it put the Phillies in a three-run hole. He issued just two walks, struck out 12  in six innings, and forced 16 swing-and-misses. It was his second straight start with nine or more strikeouts. But the homers were maddening.

"I think the swing and miss gives us a lot of promise for what could happen if he's able to limit even a little bit of the damage," manager Gabe Kapler said. "If he limits the damage, he's a top-of-the-rotation stud pitcher. We still haven't quite figured that out as a group. "

Friday was Pivetta's final start before Tuesday's trade deadline. He has a 6.70 ERA in 10 starts in June and July and has completed six or more innings in just three of those 10.

His strikeouts, seven of which came via his fastball, offer so much promise. But those strikeouts have been matched with inconsistency. Both of his homers came off sliders.

"A hanging slider. That's not going to play here," Pivetta said. "I've just got to execute better in those counts and stick to what I know and do best."

The Phillies will have to determine by Tuesday how they plan to attack the season's final two months. They will likely roll with Pivetta since general manager Matt Klentak said last week that he would prefer to stay out of the starting-pitcher market.

Every game matters as the Phillies chase a playoff spot and try to maintain their first-place lead. They are still 13 games over .500, but the loss cost the Phillies a chance to add to their 2 1/2-game lead over the Braves.

The Nationals moved over .500 with their third straight win and are six games back. They likely have a run left in them. One bad night does not spoil a playoff run. The Phillies just have to hope Pivetta can grow.

"We've seen it this year. It's not like we have to dream on something," Kapler said. "We've seen stretches of dominance this year and we know it's still in there because he's had flashes of dominance in each game that he's pitches. It's not dreaming on something. It's been there in our recent memory and it will be there in short order."

Odubel Herrera hit a two-run homer in the third for his 19th of the season and Rhys Hoskins singled in a run in the fifth. The Phillies didn't have another hit until the ninth inning, when they tacked on another run. They struck out 10 times and totaled just seven hits a night after having 18.

Maikel Franco went 0 for 4 after hitting two homers Thursday. Roman Quinn, who was promoted earlier in the day from triple A, grounded out in the seventh as a pinch-hitter. The Phils will welcome new addition Asdrubal Cabrera before Saturday's game.

"He's a dynamic offensive performer and has been a dynamic offensive performer for quite some time," Kapler said. "For me personally, I'm quite excited because I like the way he conducts an at-bat. He fits right in to our style of offense.

"He grinds pitchers down. He waits for a pitch to drive and he finds gaps and can hit the ball out of the ballpark. Fits right in with the Phillie-style offense we've been playing and why we were able to knock another pitcher out of the fifth inning today. Just add another bat when he's in the lineup. When he comes off the bench to get a big pinch hit for us, we know he's going to give us a quality at-bat. It's especially encouraging and our group is excited by it."

Eugenio Suarez homered off Pivetta in the second before Herrera's homer put the Phillies ahead by a run.

Scooter Gennett tied the game with a RBI single off Pivetta in the third before Williams crushed his homer to right in the fourth. Williams circled the bases and Pivetta received a new ball from Jorge Alfaro as fireworks rattled the ballpark.

The pitcher walked to the back of the mound in frustration. He retired the next three batters, two of whom went down swinging as Pivetta followed his struggles with promise. A maddening night continued.

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