SAN DIEGO – By the time Joe Saunders recovered from his first-inning troubles, it was too late for Arizona.
Saunders allowed four runs in the first, including Jorge Cantu's three-run homer, and the Diamondbacks lost to the San Diego Padres 4-3 on Sunday.
After having already given up a run, Saunders walked Chase Headley with one out. Then on a 1-2 pitch, Cantu homered into the left-field seats.
"He started being a little more aggressive after the first inning," Arizona catcher Miguel Montero said. "He got mad at himself and started throwing the ball a little bit better."
Saunders (0-4) allowed just two singles and a walk after the first as he retired 10 of the final 11 batters he faced. The right-hander gave up four runs on five hits over six innings.
"I made my pitch and I didn't think he was going to swing at it," Saunders said of Cantu's home run. "That pitch was meant to set up another pitch."
Aaron Harang (5-2) pitched seven solid innings and Padres center fielder Cameron Maybin helped preserve a late lead with a catch on Xavier Nady's long sacrifice fly in the eighth inning.
The Padres, who were shut out for a major league-high eighth time Saturday night, came out swinging against Saunders. It was San Diego's biggest first inning since scoring five times against Harang when he pitched for the Reds on July 29, 2009, at Cincinnati.
Going into this game, the Padres had scored a total of five runs in the first inning this season.
Harang, who lost his last two starts, was efficient against Arizona. The right-hander gave up two runs as he scattered eight hits. But he walked just one and got two double-play grounders.
The Diamondbacks closed to 4-3 in the eighth on Nady's sacrifice fly, but it could have been worse for the Padres.
Justin Upton reached on a one-out single off Mike Adams and went to third on Montero's single. Nady followed with a drive to the gap and Maybin made the catch as he fell to the warning track. Adams struck out Melvin Mora to end the inning.
Heath Bell pitched the ninth for his eighth save in nine chances. Bell's streak of 41 consecutive saves was snapped on Friday night when he blew a 3-0 lead in the ninth, the final two scoring on Headley's two-out throwing error.
Harang pitched into the seventh inning for the first time this season. Harang went six innings apiece when he set the franchise record by winning his first four starts. He also had an ERA of 1.88 in those starts.
But Harang was hit hard as he allowed 12 earned runs in his last two outings, including a career high-tying eight in a 8-2 loss April 26 against Atlanta.
San Diego has won 11 times in 13 games against the Diamondbacks at Petco Park since 2009.
Arizona's only big threat against Harang came in the second after Josh Wilson doubled in Mora with two outs. Saunders followed with an RBI single, the first of his two hits. But Harang got out of the inning when Chris Young lined out.
NOTES: The Diamondbacks have allowed 30 first-inning runs, second only to Cincinnati in the NL. ... Adams had his career-high streak of 15 scoreless innings snapped. ... The mothers of San Diego's Luke Gregerson, Logan Forsythe, Bell, Harang, Denorfia and Adams all threw out a first pitch to their sons. ... Forsythe made his first major league start at second base. He made his major league debut Wednesday against Pittsburgh after having his contract purchased earlier that day from Triple-A Tucson. ... Arizona manager Kirk Gibson said he will decide Tuesday who will start in place of RHP Barry Enright, who was optioned to Triple-A Reno on Thursday.