The win put the Reds back into a tie for first place in the National League Central with the idle Cardinals.
Pittsburgh had a 2-1 lead in the fourth inning before the Reds loaded the bases with none out against pitcher Brian Burres (2-2). Ryan Hanigan's run-scoring 6-4-3 double play tied the game but threatened to derail the rally.
The Reds came into the night leading the Majors with a .311 average with runners in scoring position and two out. They backed that reputation up once again.
"So far, guys have been able to turn their concentration up a notch," said center fielder Drew Stubbs, who was 3-for-4 and a triple short of hitting for the cycle. "Pitchers try to make good pitches with two outs. They zero in a little bit more than other counts. We've been able to lay off the bad ones and swing at the good ones. When you're able to do that, good things happen a lot of times."
On a 3-1 pitch, Harang lined a rocket into left field for a two-out RBI single that scored Jay Bruce with the go-ahead run. Orlando Cabrera followed by hitting a double through the gap in left-center field. Harang was running on contact and was nearing third base as Ryan Church retrieved the ball
Third base coach Mark Berry didn't hesitate waving Harang around to score. But with the pitcher listed at 6-foot-7, 265 pounds, it's easier said than done. Harang made it home standing up, just ahead of catcher Ryan Doumit's tag. Cabrera went to third base on the throw.
"I was praying I could make it home at that point," Harang said. "We don't get to run the bases that often and Berry felt like I had a good shot at scoring and tried to make it home without falling on my face.
"It'll probably be a while before you see me try to do that again. I was glad I was able to score and kind of keep the momentum going."
When he got back to the Reds dugout, a gassed Harang was greeted by his teammates.
"Um, we got a pretty good kick out of it," Stubbs said.
The inning continued with Brandon Phillips hitting a RBI single that scored Cabrera and Joey Votto drove in Phillips with a double to right-center field.
"I was dying there. Luckily they made a pitching change," Harang said. "It could have been a big factor if he got the next guy out and I had to go back out there still huffing and puffing."
Harang got extended rest as nine batters came to the plate in the five-run fourth.
"The next thing you know, that one run turned into five," Baker said.
In the fifth inning, also with two out, Stubbs notched his third hit of the night with a solo home run to left field. Stubbs also had a two-out RBI double for the Reds' first run in the second inning.
A nicely stopped hard grounder to second base prevented Stubbs from having a 4-for-4 night. But his average jumped 15 points from .203 to .218 and he's batting .415 (17-for-41) since moving from leadoff to the seventh spot.
Harang (3-5) didn't have the prettiest line of the night after he pitched 6 1/3 innings and allowed five runs (four earned) and eight hits with two walks and two strikeouts.
With Harang a little fatigued from his big run around the bases, he crossed the 100-pitch mark in the sixth and returned for the seventh. Pittsburgh got back into the game with a three-run inning, including Delwyn Young's two-run double to the right-field corner that finished Harang. Enerio Del Rosario struck out Andrew McCutchen in his Major League debut, but the runner reached on a passed ball. Garrett Jones' sacrifice fly to center field against Daniel Ray Herrera made it a two-run game.
Arthur Rhodes, in career appearance No. 800, pitched a scoreless eighth and Francisco Cordero recorded save No. 15 with a one-hit scoreless ninth.
"The main thing is we got [Harang] runs and he scored a run and drove in a run," Baker said. "He won and we won. That's the big deal. The line doesn't mean anything if you don't win."