Upton hit two home runs, giving him a team-high 22, and knocked in three runs, while Kemp had a two-run double as part of a four-run third inning to kick-start the offense.
"When we're both swinging the bats well, the middle of our lineup's dangerous," Upton said.
The Padres are 22-2 when Kemp and Upton each have an RBI in the same game. And, after holding on for a victory on Wednesday, the team has won each of its last 15 games when those two have knocked in runs in the same game.
"Getting guys on for us helps, too," Upton said.