CINCINNATI -- No pitcher in the major leagues has more wins than Gerrit Cole since Sept. 7. But the Pittsburgh Pirates right-hander has been unable to solve his chief nemesis, the Cincinnati Reds.

Rookie right-hander Raisel Iglesias pitched six solid innings and shortstop Eugenio Suarez drove in a career-high three runs, lifting Cincinnati to a 4-3 victory over the Pittsburgh Pirates on Saturday night at sold-out Great American Ball Park.

Shortstop Jung Ho Kang homered for Pittsburgh (60-43), which dropped to 3-9 against the Reds this season.

As for Cole, he remained winless in six career starts against Cincinnati after allowing three runs (two earned) and seven hits in five innings.

He walked one and struck out eight but needed 98 pitches to get through five innings.

"I'm very frustrated," said Cole, who's now 14-5 on the season. "They've got me every time. But you have to honestly evaluate and find stuff to move forward with. I thought there were some mistakes that need to be corrected. There weren't a ton."

Left fielder Marlon Byrd tripled and scored twice for Cincinnati (47-55), which has won five of six.

Iglesias retired nine straight after Kang's homer, but he ran out of steam in the sixth.

After Travis Ishikawa's pinch-RBI single cut the Reds' lead to 3-2, Burke Badenhop replaced Iglesias and fanned pinch-hitter Francisco Cervelli to end the inning.

Iglesias (2-3) allowed two runs and four hits in 6 2/3 innings.

With five rookies in the starting rotation, Reds manager Bryan Price said he's striking a delicate balance.

"First of all, he was throwing the ball well," said Price of Iglesias. "I felt like when they pinch-hit with Ishikawa, the matchup was still a good one. Regardless of age and experience we need to teach our young starters to keep themselves in the game. I'm not going to force-feed them those innings. They have to earn them. We can't throw the life-preserver in every single situation."

Cincinnati added an insurance run on Suarez's sacrifice fly in the eighth against right-hander Joe Blanton, who was making his Pirates debut after being acquired from the Kansas City Royals on Thursday. Blanton pitched two innings and allowed a run and two hits with two strikeouts.

The Reds needed that extra run after the Pirates, who were down to their final strike three times in the ninth, rallied against Reds closer Aroldis Chapman.

On a 1-2 pitch, pinch-hitter Sean Rodriguez delivered a two-out RBI single. With the bases loaded, Chapman fanned left fielder Starling Marte on a 2-2 pitch for his 22nd save of the season.

"We had really good at-bats against Chapman in the ninth and put ourselves in position to do something significant," manager Clint Hurdle said.

Marte, who threw a runner out at the plate and made a diving catch in the ninth inning on Friday night to preserve a 5-4 win, picked up where he left off by diving to snare right fielder Jay Bruce's liner in the first inning.

Cole has been dominant this season while becoming one of only three Pirates pitchers to have 14 wins and a 2.24 ERA after 20 starts.

But he is 0-2 with a 6.75 ERA in three starts against the Reds this season.

Cincinnati got to Cole in the second when Byrd led off with a triple past Andrew McCutchen in center and scored on Suarez's sacrifice fly for a 1-0 lead.

The Pirates tied the score 1-1 in the fourth when Kang crushed a 2-2 pitch from Iglesias into the left-field bleachers for his eighth home run of the season.

"I was very upset in that moment," said Iglesias, with catcher Brayan Pena interpreting. "I just went back out there and focused. I was very happy to help the team win and go deeper in the game to give the bullpen a rest."

The Reds regained the lead in the bottom of the fourth on Suarez's RBI double.

Bruce's two-out double drove home second baseman Brandon Phillips in the fifth, putting Cincinnati up 3-1.

"So far, (the Reds) have confidence against a couple of our starters," Hurdle said. "They have confidence when they go up against Gerrit."

NOTES: Reds LHP Aroldis Chapman has converted 55 straight save opportunities at Great American Ball Park ... Pirates LHP J.A. Happ arrived in Cincinnati on Saturday and threw his first bullpen session since being acquired from the Mariners on Friday. Happ will make his Pittsburgh debut on Tuesday against the Cubs. ... To make room for Happ, the Pirates optioned LHP Bobby LaFromboise to Triple-A Indianapolis a day after he was recalled. ... Reds manager Bryan Price announced that rookie RHP Keyvius Sampson will make his first career start on Sunday against Pittsburgh. ... With Sampson, Cincinnati now has five rookies in its starting rotation. His start will be the 51st made by a Reds rookie this season, the most since 2001.