WASHINGTON - A day off in Pittsburgh on Thursday will end a stretch of 20 Phillies games played in 20 days, and Rich Dubee is not about to let that rest go to waste.

So instead of skipping the fifth spot in the rotation vacated by Vance Worley's demotion to the minors, Kyle Kendrick will pitch in his turn Saturday, thus providing the Four Aces with an extra day of rest.

"Cliff Lee threw 122 pitches in the heat the other day," said Dubee, the pitching coach. "[Roy Halladay] has been going deep into games. [Cole] Hamels has been going deep into games. We're going to take advantage of the off day."

To do that, Kendrick will make his third start of the season. The righthander was effective in one of those spot starts and dismal in the other. His last outing was Sunday, a three-inning, 33-pitch effort in relief of Worley.

The Phillies expect Kendrick to muster around 65 pitches. The obvious question then becomes: What's the advantage of pitching Kendrick, who is not stretched out, when the problem cited with Worley was his lack of stamina?

"The advantage is we need to get Vance Worley going right again," Dubee said. "This is probably more for Vance than anything. Personally, I think he kind of got messed up when we put him in the bullpen for that little period there. He was going pretty good and then he went to the bullpen and lost his edge, his stamina, his endurance."

Worley will start Friday for triple-A Lehigh Valley. The 23-year-old rookie said he expected to be back soon with the Phillies, but the team needs to see him regain arm strength before that happens.

Until then, Kendrick will slide into the rotation. His 3.18 ERA is a bit deceptive considering his poor strikeout-to-walk ratio (12 to 13). His opponents' unusually low .247 batting average on balls in play suggests a great deal of luck is bouncing Kendrick's way.

More roster talk

An intriguing personnel decision still looms Friday, when Shane Victorino is likely to rejoin the team after a weeklong rehab from a strained right hamstring.

Charlie Manuel said he could envision going to 11 pitchers, but Dubee reiterated his desire to stick with 12.

That leaves Michael Martinez and John Mayberry Jr. as the likely candidates for demotion. Mayberry has an option remaining while Martinez must pass through waivers before being offered back to Washington because of his Rule 5 status.

Manuel said remaining options could come into play in deciding who stays and goes. He also offered support for Martinez.

"It's hard for us to play him a lot right now," Manuel said. "But I liked what I saw in spring training, especially the way he played the infield. It would be nice if we could play him more. I look at Michael and [Wilson] Valdez as two utility players. In the National League, especially the way our team is right now with [Chase] Utley's situation, we might need a baserunner late in games. It doesn't mean Michael is going to be the guy. We haven't really gone over it yet."

Extra bases

Victorino played in his third rehab game, this time with double-A Reading, and was 0 for 4 with a strikeout. . . . Brad Lidge (rotator cuff) threw another inning in an extended spring training game. But Dubee said the former closer topped out at 87 m.p.h. and still has a ways to go. . . . The Phillies recalled lefthander Mike Zagurski before Tuesday's game to fill Worley's roster spot.