With the scored tied at 3, and runners on second and third with one out in the ninth, Bako chopped a slow roller to Phillies shortstop Jimmy Rollins who fielded the ball on the edge of the infield grass but was unable to make a play. Freel scored from third, and Bako was credited with a game-winning single.
"I'm just glad things worked out there," Bako said. "The pitch was outside. It probably would've been ball three. I took a chance."
Bako, filling in for the injured Javier Valentin, went 3-for-4 on Saturday, after beginning the season 0-for-7.
"Bako's been on a few teams that have won," Baker said. "He was a tremendous acquisition for the ballclub. He calls a good game. Whatever we get from his bat is extra."
The Reds are now 3-0 in one-run games this season.
"Good teams have to be versatile," said Reds center fielder Corey Patterson. "You have to have guys who are contact hitters, guys who can steal bases, and guys who hit for power. One-dimensional teams don't make it too far."
Patterson's unique combination of speed and power was evident throughout Saturday's game.
In the first inning, Patterson, who went 1-for-3 with two runs scored, including a solo home run, walked, stole second, advanced to third on a groundout, and scored on Ken Griffey Jr.'s sacrifice fly to put the Reds ahead, 1-0.
First baseman Scott Hatteberg's RBI single in the second inning drove home Adam Dunn to make the score 2-0.
Reds ace Aaron Harang, looking for his first victory of the season, battled for seven innings, allowing two runs on six hits. He walked three and fanned six in his second quality start in as many showings.
Philadelphia scored its first run when Shane Victorino tripled with one out in the third, scoring on Chase Utley's double.
Following Utley's double, Harang retired eight consecutive Phillies batters.
"They're a good hitting team," Harang said. "I tried to keep mistakes to a minimum. I was able to hold them off and give us a chance to win."
Harang pulled a high-wire act in the sixth.
Utley singled and Ryan Howard walked with one out. Pat Burrell followed with an RBI double to left, driving in Utley to tie the score at 2.
Geoff Jenkins walked to load the bases.
Harang then struck out Greg Dobbs on three pitches, and got Chris Coste to hit a lazy pop fly to second baseman Brandon Phillips to end the inning.
"That's huge, right there," said Baker. "He got out of some trouble. Getting out of that bases-loaded jam was key. We want Aaron to get on the board with that first win, but we'll take the team victory."
The victory appeared to have eluded the Reds when Howard powered a 479-foot home run to center field off Reds left-hander Kent Mercker to put the Phillies ahead, 3-2.
Howard's homer landed just below the smoke stacks in center, equaling the sixth-longest home run in Great American Ball Park history.
"Mercker's been throwing the ball well," Baker said. "He gave up a home run to a home run man. Howard is going to hit his home runs."
Patterson answered in the Reds' ensuing at-bat with a solo home run, his second of the season, which sailed into the home bullpen to tie the score at 3. The homer, off Phillies starter Adam Eaton, was the 96th of Patterson's career.
Later in the inning, the Reds had the lead runners in scoring position, but Phillies reliever Tom Gordon fanned Phillips with runners on first and second.
Phillies right-hander Chad Durbin (0-1) took the loss.
Durbin began the ninth by walking Adam Dunn, who was pinch-ran for by Freel. He then walked Edwin Encarnacion.
Pinch-hitter Norris Hopper's perfectly-placed sacrifice bunt down the third-base line advanced the runners to second and third, setting up Bako's heroics.
Francisco Cordero (1-0) pitched a perfect ninth inning to earn his first victory in a Reds uniform.
"One win is no more important than another," said Patterson. "But it is good to get off to a good start. The long ball's not always going to be there. You have to get on base any way you can. You want to develop good habits and a positive attitude early."