The Phillies will give Diekman and Justin De Fratus a month to join the bullpen carousel of auditions. Both were recalled from triple-A Lehigh Valley, which has been eliminated from postseason contention.
The relief corps now consists of nine pitchers, seven of whom are age 26 or younger.
"We're going to take a look at all of these guys," manager Charlie Manuel said.
Both Diekman and De Fratus have major-league experience. Diekman, 25, pitched in 23 games earlier this season until control issues dictated a demotion. De Fratus, 24, appeared in five games last September and was expected to play a role in 2012 until elbow problems derailed much of his season.
Diekman's penchant for walks continued once he was in the minors again. In 12 outings for Lehigh Valley after being optioned, he struck out 15 and walked 10 in 111/3 innings. His ERA was 3.18.
He walked 15 in 211/3 innings with the Phillies, and that was the reason for his demotion.
"I knew they did it for a reason, and I knew what the reason was," Diekman said. "So I just needed to go down there and work on it."
Diekman believes he turned a corner after studying video with IronPigs pitching coach Rod Nichols and altering his set position on the rubber. That, along with a conscious effort to stop nibbling early in counts, has him confident.
De Fratus said he is simply grateful for his return. He started the season on the disabled list with a strained flexor pronator tendon in his right elbow, an injury that typically requires surgery.
He did not pitch at triple A until July and displayed pinpoint command there. He had 22 strikeouts against three walks for a 2.49 ERA in 212/3 innings. Had De Fratus been healthy, his major-league promotion would have come sooner.
"I'm not even thinking about it that way," De Fratus said. "With the way the year started, I feel very blessed to be back here, that's for sure."
Still no Brown
Domonic Brown was missing from Manuel's lineup for the seventh time in eight games. Brown's sore left knee, an injury that was originally thought to be minor, has prevented him from a full workload.
Manuel said Brown should reappear before Wednesday, when this road trip ends. The 24-year-old outfielder has pinch-hit in four of the games he has not started.
"I'm trying to get him ready to play," Manuel said. "We don't want him to play when he's hurting. We want to look at him."
With two hits Sunday, Jimmy Rollins is two away from reaching 2,000 for his career. Only three players have ever achieved 2,000 hits as a Phillie - Mike Schmidt, Richie Ashburn, and Ed Delahanty. . . . With lefty Paul Maholm pitching, Manuel used his unorthodox outfield trio of Ty Wigginton, John Mayberry Jr., and Michael Martinez for the third time in four games.
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