PHILADELPHIA—It felt a little premature.

Save for two pitches, solo home runs in the second and fifth, Phillies starter Jonathan Pettibone was going strong in his big league debut.

And after getting Andrew McCutchen to ground out for the first out of the sixth, the 22-year-old right-hander was at only 83 pitches, more than enough to get two more outs.

But Pettibone hadn't yet been stretched out at Triple-A, and two lefties were due up.

So Charlie Manuel thumped his back and took the ball, passing it along to relievers Raul Valdes and Antonio Bastardo, set-up man Mike Adams and closer Jonathan Papelbon.

They handled the rest.

The four combined for 3 2/3 scoreless innings to secure a 3-2 win over the Pittsburgh Pirates at Citizens Bank Park tonight, for the Phillies third win in four games, second series opening win in seven this year and first since April 12 in Miami.

"Bullpen was real good," Manuel said.

They didn’t get beat tonight. They didn’t get worn out for the rest of the series.

Instead, they began to plead their case in earnest that this relief staff can be trusted – maybe even as early as the sixth inning.

Ask yourself: what seemed less likely coming in?

That Pettibone would surrender only two runs in 5 1/3 innings? Or that the bullpen could secure a one-run lead for almost half a game?

How they fare for the rest of the year remains to be seen. But the Phillies ‘pen is working 12 1/3 scoreless innings streak, spanning back to Carlos Beltran’s eighth inning jack off Mike Adams for the go-ahead run in a loss against the Cardinals last Thursday.

Papelbon retired back-to-back batters in the ninth with a man on second for his fourth save of 2013 in as many tries. He’s 55 for 55 in save opportunities in his career in April.

Adams, who only three days ago said he wished he “felt a little better” coming off offseason shoulder surgery, punched a 12-pitch, 1-2-3 eighth inning.

Bastardo served a leadoff infield single to Pedro Alvarez in the seventh, but got Russell Martin to ground into a double play and gassed by Clint Barnes to end the frame. Bastardo has only surrendered two hits in 7 1/3 innings so far, without an earned run.

That’s the procession Manuel needs to get from his starters to wins.

Valdes and Chad Durbin, who pitched well yesterday, too, may be adding to that. Valdes fanned Garrett Jones and Neil Walker in back-to-back at-bats to end the sixth.

Valdes still has an ERA north of 10.00. He’s twice allowed four runs or more in 3 1/3 innings or fewer. Though this does make two scoreless outings in his last three.

Pettibone outshined his early minor league performance, maybe enough to earn a second (or third) start in place of John Lannan. Who knows. Manuel wouldn’t say after.

“Man, I don’t know,” Manuel said. “We’ll have to think about it. We’ll talk about it.”

Pettibone entered having allowed 10 runs in 9 1/3 innings in two starts with Lehigh Valley this year. But he stuck six strikeouts tonight, the most for a Phillies starter in their ML debut since Cole Hamels fanned seven his first time out in 2006.

"He did fine," Manuel said.

"For being a young guy, first time pitching in the big leagues, he made some pitches at times. Early, they hit some balls hard on him. But he got 'em out when he had to, too."

For his first, Pettibone fanned Andrew McCutchen his first time up, after going down 3-0.

Team defense helped him. John Mayberry Jr., laid out for a rope by Garrett Jones to get the third out of the first and strand Starling Marte at third base. Domonic Brown in the second gunned out Russell Martin, who tried to take an extra bag, at second base.

But Pettibone's poise was key.

Marte smeared a double to center on Pettibone’s second big league pitch. Then came the bombs, from Alvarez and Martin.Of 14 balls in play, just four were grounders. Most of the rest were the type of deflating line drives and fly balls that rattle young pitchers easily.

"I thought what really got him by was that he started getting firm with his fastball," Manuel said.

"That was kind of the game plan, just being aggressive," Pettibone said. "I didn't want to kick around the strike zone. I wanted to get ahead of guys, go after guys. Pitch to my strengths."

Pettibone helped his cause, scored himself on a wild pitch from Pirates starter A.J. Burnett in the third inning after walking in his first big-league plate appearance.

Beyond that, the lineup was again active but not productive. They had 12 base runners tonight, and worked all of them in scoring position.

With them there, the bats mustered only two hits.

In three straight frames they opened with men on first and second and no outs, with their first three batters loading the bases to start the fourth. That yielded two runs, total.

Jimmy Rollins took a Burnett pitch in the leg in the fourth to walk home Michael Young, put the Phillies ahead, 2-1, lead and keep the bags full for John Mayberry, who struck out and stranded four total. That, and the Pettibone scamper, was all.

But Rollins zipped the go-ahead RBI single to score Erik Kratz in the sixth, after the bullpen had gone to work.

In lieu of big-time pop, and with Pettibone or another young arm for the 6-8 Lannan needs to heal, that could be the formula for the not-too-distant future.

It's predicated on the bullpen performing, exactly as they did tonight.