Samardzija is 2-1 with a 4.13 ERA in four starts this season, but he has had some high pitch counts, including 110 in his first start, and the Cubs have decided they want to give him an occasional break when the opportunity presents itself.
Such an opportunity presented itself when a break in the schedule allowed the Cubs to keep Chris Volstad on a five-day schedule, and start Monday's 6-4 loss to the Phillies.
By moving him back a day, Samardzija will now wait a full week between starts, as the Cubs try to preserve him as he adapts to his new routine as a starter.
"Any time we can use that to our advantage, and see if we can monitor the pitch counts and innings, it's just going to benefit him in the long run," manager Dale Sveum said.
Samardzija will face a Reds team that finished April at .500 (11-11) despite the fact the team's offensive performance has been spotty. The Reds were off on Monday.
"As a team, we're in good position considering we haven't hit yet," manager Dusty Baker said. "It's been a tough month on the head and the heart with the tough games we've lost."
Samardzija will oppose Reds right-hander Bronson Arroyo, who is 1-0 with a 2.70 ERA in his first four starts.
Cubs: Campana providing a lift
Since being recalled from Triple-A Iowa on April 21, center fielder Tony Campana has hit safely in seven of nine games, and he has stolen seven bases without being thrown out.
Reds: Cairo might be back
Outfielder Miguel Cairo could be activated Tuesday from the disabled list (strained left hamstring). He was eligible to come off Monday, when the team is off.
"I feel good, but I think I have to run the bases first," Cairo said Sunday. "I don't know the plan. I wish I could tell you. The good thing is, I feel good and my legs feel good. We'll see what happens on Tuesday, Wednesday or whatever."
Veteran Reds third baseman Scott Rolen is batting only .186, but has shown signs of coming out of his funk, having hit the ball hard of late. Rolen hit his first two homers on Wednesday and Thursday, and Friday he crushed the ball three times for outs. He appeared only as a pinch-hitter in the Reds' last game Sunday, and walked, but is scheduled return to the lineup Tuesday.
"He's hit the ball a lot better than his average indicates," Baker said. "There are some guys that have good averages and you know they're going to fall off the cliff any minute because they get bleeders, choppers and bloopers. He's been the guy that's probably hit the ball the hardest with the least amount of success."