SAN DIEGO -- Rookies Jedd Gyorko, Tommy Medica and Chris Robinson homered, and San Diego pitcher Ian Kennedy beat his former team for the first time as the Padres rolled to a 12-2 rout of the Arizona Diamondbacks at Petco Park on Wednesday night.
Kennedy was traded from the Diamondbacks to the Padres on July 31, and he struggled when he pitched Aug. 27 at Chase Field, allowing six runs in 4 1/3 innings. Kennedy (7-10) enjoyed a smoother performance Wednesday, giving up two runs on six hits with seven strikeouts and a walk in seven innings.
A four-run surge in the fifth inning sparked the Padres, who got a two-run single from Chris Denorfia and a two-run home run by Gyorko. San Diego continued to pour it on with single runs in the sixth and seventh innings and four more in the eighth.
Robinson's three-run homer in the eighth was his first major league hit. Chase Headley went 3-for-5 with three RBIs, and Rene Rivera finished 3-for-4 with an RBI.
Arizona starter Randall Delgado (5-7) gave up six runs on seven hits in five innings.
The Padres (74-84) beat the Diamondbacks (80-78) for the seventh time in nine meetings at Petco Park.
San Diego outhit Arizona 14-6.
Headley gave the Padres a 1-0 lead with two outs in the first on a double to right that bounced out of the glove of a sprinting Gerardo Parra, scoring Denorfia, who also doubled.
Delgado's single to center drove in Parra to tie the score with one out in the third.
In the fourth, the Diamondbacks took the lead on a balk by Kennedy, allowing Paul Goldschmidt, who doubled and advanced to third on a single by Martin Prado, to come home for a 2-1 advantage. Goldschmidt's double extended his hitting streak to 15 games, the longest in the majors.
Medica tied the score again with a solo home run that traveled an estimated 411 feet to right on a 3-1 pitch from Delgado with two outs in the fourth.
Denorfia's two-run single with two outs in the fifth put the Padres back on top, 4-2.
Gyorko followed with a two-run shot -- his 21st of the season -- into the upper deck in left for a four-run cushion.
NOTES: Padres OF Will Venable returned to the lineup after missing the past two games with an abdominal strain. He finished 1-for-4 with two runs. ... San Diego SS Ronny Cedeno didn't play again as a precaution after being hit in the head by a pitch from Arizona RHP Heath Bell on Monday night. The Padres said Cedeno is day-to-day. ... Diamondbacks RHP Trevor Cahill (8-10, 4.02) will face Padres LHP Robbie Erlin (3-3, 4.34) in the series finale Thursday. The game also will complete the Padres' final homestand of the season. ... Sports broadcaster and San Diego-area resident Jim Lampley threw out the first pitch.