Because Saito was on the 60-day disabled list with an elbow injury, he did not count against the 40-man Major League roster. So, to facilitate his activation, the club needs a roster spot. Manager Joe Torre said it had not yet been decided who would come off.
Torre said Saito would first pitch an inning "when it is insignificant, for the first go-round" and would not be used on back-to-back days.
Torre said he also expects to have Hong-Chih Kuo available Saturday. Kuo has not pitched since throwing 1 1/3 innings Sunday against Arizona. On Wednesday, he received a cortisone shot in his twice-rebuilt elbow.
"It is fatigue," Torre said. "He got a shot yesterday. It's already made him feel better. It's the time of year, in a role he hasn't had before."
Speaking of unfamiliar roles, Torre said Brad Penny will continue pitching relief. Penny's first bullpen appearance since the 2006 playoffs lasted three batters Wednesday -- a walk, a broken-bat bloop single and an infield single.
"The other day, he was a little tentative," Torre said of Penny. "A walk, a bloop and a ground ball. We couldn't afford to see any more. He'll get another shot at it. As long as he feels good, and that seems to be the case, I still think he can really benefit us picking up an inning or two."
Penny, however, has said he wants to start, not relieve.
"Down the road? Who knows?" Torre said. "We'll see how many innings he throws and if we want to change things starter-wise, we'll go there. We've got a little work to do first."
Penny will not pitch on back-to-back days and might need two days off between appearances.
Torre had no more clarification on the status of Rafael Furcal, who appeared pretty rusty during Saito's simulated game Wednesday.
"We have to figure out, when he's ready to play a game, what do we do about it," he said, alluding to the lack of a Minor League rehab assignment as an option.
Injured catcher Gary Bennett, scheduled for a sonic shock treatment on his plantar fasciitis next week, has been assisting scout Vance Lovelace on this trip.
Back in Los Angeles, Jeff Kent continues rehabilitating from left knee surgery and Torre said the second baseman has begun hitting off a tee. Kent will not be in Denver or Pittsburgh, but Torre said there is a chance Kent will be ready to take batting practice when the Dodgers return home next weekend.
"It will be 2 1/2 weeks [after surgery] at that point and we'll see how long he'll be from there," he said.
That will help determine if Kent would be available for the postseason, at least for a bench role. Torre said the calf discomfort Kent reported following surgery is "better, but not gone."
Ken Gurnick is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.