Phillies' Kendrick may be out two weeks with strained oblique

Howie Kendrick's absence may be longer than first anticipated as the team announced on Friday afternoon that Kendrick has a strained oblique muscle.

The injury - which plagues the outermost muscle of the abdomen - often requires a recovery longer than 10 days, the time period the Phillies hoped Kendrick would miss after he was placed earlier this week on the disabled list. He is eligible to return on Wednesday.

"Maybe two weeks," Phillies manager Pete Mackanin said. "It's day by day, but obliques are precarious. Even when you feel good, one little twitch can reactivate it."

Kendrick, who joined the Phillies in an offseason trade and is a free agent after the season, is batting .333 with a .395 on-base percentage in his first 39 at-bats. The 33-year-old outfielder told Mackanin when he went on the DL that he thought the injury was his chest and not his oblique. Kendrick suffered the injury while throwing. An oblique tends to keep a player sidelined for about four weeks.

The Phillies will likely promote an outfielder from triple A if Kendrick's absence is prolonged. They are playing with a shorthanded bench after promoting relief pitcher Mark Leiter Jr. when Kendrick went to the DL. In the meantime, Kendrick's absence will provide playing time for Daniel Nava and Aaron Altherr, who started in left field on Friday night against Atlanta.

"We're going to miss him. We already miss him," Mackanin said. "But it is good to get the other guys at-bats, and they are both swinging the bats well."

Knapp impresses

Andrew Knapp drove in his first career run with a key double in Thursday's series finale in New York, but it is his defense that impresses Mackanin. Knapp's growth behind the plate will be what allows Mackanin to use him more often.

"I like the way he caught," Mackanin said. "He can handle himself behind the plate. When you are not playing on a regular basis, I'll take a 1 for 4. He looks like he can hit. I've got to try to keep him sharp by giving him as much playing time as I can. But right now, Rupp is the guy that I can lean on."

Extra bases

Jerad Eickhoff pitches for the Phillies on Saturday night against lefthander Jaime Garcia, who has a career 2.82 ERA in 10 games against the Phillies. . . . The Phillies entered Friday leading all of baseball with 4.05 pitches per plate appearance. They ranked 27th last season with 3.81 pitches per plate appearance.

mbreen@phillynews.com

@matt_breen www.philly.com/philliesblog