Hundley's home run came in the fourth inning against Dodgers starting pitcher Clayton Kershaw, who is coming off a season in which he was the runner-up for the National League Cy Young Award.
Kershaw allowed one run over the first three innings but yielded three runs with no outs in the fourth inning, one on an RBI triple by Kyle Blanks and two on Hundley's home run, which ended his day. Kershaw allowed seven hits, one walk to go with two strikeouts.
San Diego starting pitcher Jason Marquis, who will likely be the No. 3 starter in the rotation, allowed one earned run on four hits in three innings. He walked two and struck out two.
Marquis, who has added a changeup this spring, has worked with former Padres closer Trevor Hoffman on the pitch and grip. Of the 57 pitches he threw Tuesday, 12 of them were changeups.
"Stamina-wise, I felt good," Marquis said. "I was a little sharper the last time out. But I made better adjustments as the game went on."
The Dodgers got an unearned run off Marquis in the first inning and Dee Gordon singled in a run in the second inning.
The Padres got an RBI single by Yonder Alonso in the bottom of the first inning, as he took a Kershaw fastball to left field.
Two innings after Hundley's home run, teammate Maybin added his first home run of Cactus League play. Guzman did the same in the seventh inning.
Maybin and Chase Headley each had two hits. Hundley is hitting .571 this spring.
Matt Kemp went 0-for-3 in his first start in the Dodgers' outfield since undergoing left shoulder surgery. He was replaced by Yasiel Puig in the bottom of the fifth.
Brian Barden had two hits for the Dodgers.
Up next: The Padres are off on Wednesday, their first off-day of the spring. They face the Angels at 12:05 p.m. PT on Thursday at the Peoria Sports Complex. Rotation hopeful Freddy Garcia gets the start and will likely work three innings. Garcia, in camp on a Minor League deal, has allowed seven earned runs on nine hits in 3 2/3 innings. Casey Kelly, another rotation hopeful, will follow Garcia with two innings. Kelly has allowed four runs in four innings.