With San Diego starting right-hander Dustin Moseley Saturday and left-hander Clayton Richard on Sunday, Mattingly said he started left-handed hitting Tony Gwynn in left field to give Rivera a day off while planning to start Rivera Sunday against Richard.
"I noticed last year, I kept banging [Rivera] and it wore him down a little bit," said Mattingly.
Left-handed-hitting Adam Kennedy started at third base for Uribe, who is 1-for-7 lifetime against Moseley.
"[Uribe]'s going to be streaky," said Mattingly. "I won't let two games [0-for-7 with a walk and two strikeouts] determine how I feel about this guy. He's going to get his at-bats, he'll get his chance. I really don't have anyone who can play there every day. He's our best defensive guy there."
Mattingly said the roster moves over the winter -- most notably the signings of Kennedy and Jerry Hairston Jr. -- will allow him to mix and match based on the opposing pitchers and the schedule, which he noted has the Dodgers playing 30 day games after night games.
"I like fresh guys over the course of the season," he said. "We have a bunch of day games after night games. Fresh teams occasionally win those games. Guys get tired."