CINCINNATI -- Reds right-hander Robert Stephenson faced runners on second and third base with no outs in the third inning on Sunday afternoon.

With 17 starts under his belt in the major leagues, the 23-year-old rookie approaches those situations differently.

"A year ago, I would have just thrown the ball over the plate and tried to find contact," he said. "I've gotten a lot better in those situations, knowing I can bear down and get them out with my best stuff."

Stephenson retired three straight batters to escape that jam en route to cruising through six shutout innings in a 5-2 victory over the Pittsburgh Pirates at Great American Ball Park.

Eugenio Suarez and Scooter Gennett each hit two-run homers helping the Reds (66-84) complete a three-game sweep.

Stephenson (5-5) allowed one hit, walked three and struck out eight.

"The first three innings, he was all over the place, and my concern was when to pull the plug," Reds manager Bryan Price said. "But, in innings four and five, here we come. That's what you want to see. I was really impressed with how he handled those struggles."

Michael Lorenzen pitched a 1-2-3 ninth inning to earn his second save.

The Reds swept the Pirates for the second time this season and for the first time at Great American since 2015.

Cincinnati has spent 96 straight days in last place in the National League Central, but now trails the Pirates by only two games in the standings.

"We should strive for a lot more, but of course it's important," Price said. "We want to get back talking about the top of the division than where we are. But these games have importance."

John Jaso homered for Pittsburgh (68-82), which has lost five straight. The Pirates finished the season 6-13 versus Cincinnati.

For the second straight game, there was a pitcher's duel in a ballpark that doesn't often lend itself to well-pitched games.

Pirates starter Gerrit Cole (11-11), who went winless in his first nine career starts against the Reds before beating them on Aug. 26, came into Sunday's start 1-7 with a 4.79 ERA against them.

Cole homered in his last start at Great American Ball Park. He doubled in the second inning on Sunday to put runners at second and third.

But Stephenson retired three straight batters to escape the only true jam he faced in his six innings.

Stephenson struck out four consecutive batters at one point, and Cole matched him pitch for pitch through five innings.

Cole allowed four earned runs on three hits with four walks and six strikeouts through five-plus innings on Sunday.

"His overall execution was solid," Pirates manager Clint Hurdle said. "They took advantage of a couple of pitches, and this ballpark. Suarez's would've been out anywhere. Gennett's would've hit our wall. He used four pitches. He gave us what we needed."

But Cincinnati teed off on Cole in the sixth.

Suarez put the Reds ahead 2-0 with his 26th home run following Jesse Winker's walk. After Joey Votto walked, Gennett launched his 25th home run, making the score 4-0.

"I just didn't make enough good pitches to Winker to start the inning," said Cole. "I didn't put myself in a good position by walking the leadoff hitter. I made a mistake to Gennett. They're looking to slug. They're looking to do some damage. They put good swings on some balls."

Tucker Barnhart added an RBI triple off Daniel Hudson for the Reds' fifth run.

Jaso's two-run home run off Luke Farrell in the eighth was his 10th of the season. The homer tied Jaso's career-high established in 2010.

But, it was all the offense Pittsburgh could muster on Sunday.

"The pitching against us lately has been good," Hurdle said. "We haven't pushed on anybody for a while."

NOTES: Reds RHP Drew Storen will undergo Tommy John surgery. Recovery could extend through the 2018 season. ... Reds CF Billy Hamilton was eligible to come off the disabled list on Sunday but did not. He is having the splint removed from his fractured hand and can resume baseball activity. ... Pirates C Francisco Cervelli (quadriceps) will meet with coaches and trainers on Monday to determine his status for the rest of the season. ... The Reds have five players with 25 or more home runs, tying a club record set in 1956.