"We've improved in a lot of ways," Sandberg said. "The bullpen has been one of the biggest things that has really come along the last two weeks."
The Phillies' bullpen has a 4.33 ERA on the season (last in the National League) entering Friday, but it is 3.94 in August. Two rookie relievers -- left-hander Jake Diekman and right-hander B.J. Rosenberg -- have been particularly impressive.
Diekman has tossed nine scoreless innings over his last nine appearances dating back to Aug. 11, allowing five hits with 14 strikeouts and one walk.
Rosenberg has held opponents scoreless in seven straight appearances since being recalled from Triple-A Lehigh Valley on Aug. 16. Opposing hitters are batting .130 (3-for-23) against him over that stretch.
Both Diekman and Rosenberg continued their hot streaks in Friday's 6-5 win. Diekman walked a batter, but didn't give up a hit in two-thirds of an inning, while Rosenberg won his first game of the season and second of his career after pitching a scoreless eighth with two strikeouts.
The Phillies' bullpen, which also included Zach Miner and Jonathan Papelbon, who earned his 23rd save, threw four scoreless innings.
Catcher Carlos Ruiz said it's nice to see the young arms performing well, and that the key for them has been getting more comfortable at the big league level.
"It's good to see [the recent success]," Ruiz said. "We have a lot of young guys in the bullpen right now, and they're learning about how to be here in the big leagues. It's fun to see that, because now they feel more comfortable and relaxed. I hope they continue to stay that way and finish [the season] strong."
Manny Randhawa is an associate reporter for MLB.com. Follow him on Twitter at @MannyBal9. This story was not subject to the approval of Major League Baseball or its clubs.