Philadelphia leads the National League East by six games, but the Braves’ lead in the wild-card race is even wider. If they beat their first-round opponents — at the moment, the Phillies would play Arizona and the Braves would play Milwaukee — the N.L. Championship Series could be problematic for the Phillies.

The Braves and the Phillies have split 12 games this season, and the Phillies easily have the majors’ best rotation. But the Braves are not far behind, and in O’Flaherty and Venters, the Braves could neutralize the Phillies’ left-handed sluggers. Chase Utley has hit .224 against lefties this season, and Ryan Howard has hit .240, with only 3 of his 27 home runs.

“I don’t think the bullpen’s our No. 1 strength; I think it’s our rotation,” Venters said. “They’re going to keep us in ballgames. That’s what’s been huge all year, and scoring runs when we needed to. But the bullpen has done its job.”

Venters was such a revelation last season that Billy Wagner, then the closer before retiring with 422 career saves, said he was “better than I ever was” because of his 95-mile-an-hour sinker. Venters has 83 strikeouts in 742/3 innings, but says he tries to use the sinker to induce soft contact and get quick outs.

Even so, it is a power pitch, and fitting for the mentality Venters has always had. An outfielder and pitcher at Indian River Community College in Florida, Venters was drafted in the 30th round in 2003. He had athleticism, but not much else.

“I wasn’t very good,” he said. “I didn’t throw very hard. I didn’t throw a lot of strikes.”

Venters failed as a starter in the minors, unable to stay healthy or sustain much success. But his velocity spiked as a reliever, and he discovered he was suited for that role all along.