Updated

Clayton Richard pitched eight innings and the San Diego Padres matched a season-high with their sixth straight win, 9-3, over the Arizona Diamondbacks Saturday night.

Chase Headley, Carlos Quentin and Yonder Alonso homered off Ian Kennedy, as the Padres won their sixth in a row at Chase Field.

Richard (11-12) gave up seven hits and three runs, including a pair of homers. The lefty has won four of his last five starts, and has pitched at least eight innings in three of those games. He's 5-0 in seven career games against the Diamondbacks.

Justin Upton, who celebrated his 25th birthday Saturday, hit a two-run inside- the-park homer for Arizona. Aaron Hill also went deep for the Diamondbacks, who will try to avoid the three-game sweep Sunday.

Kennedy (11-11) allowed four hits and six runs over 5 1/3 innings to lose for the first time in seven career decisions against the Padres.

Headley homered to right field in the opening inning, but in the bottom of the second Upton got a fortunate bounce to turn it the ninth inside-the-park homer in franchise history.

Paul Goldschmidt walked, and then Upton hit a ball to the 413-foot sign in right-center field. The ball took an odd carom past center fielder Cameron Maybin and Upton scored without a throw to the plate.

Quentin homered to center in the fourth and Alonso started the next inning by taking a 1-2 pitch over the wall in right field.

"When he started out he threw the ball good but obviously the home runs hurt him," Diamondbacks manager Kirk Gibson said of Kennedy.

San Diego loaded the bases with one out in the sixth inning and Kennedy walked Yasmani Grandal to increase the margin to 4-2. Alonso followed with a two-run single into right field. Quentin made a tumbling slide at the plate to avoid the tag from Miguel Montero.

A pair of sacrifice flies and a bases-loaded walk in the eighth increased the difference to 9-2 before Hill homered off Richard in the bottom of the inning.

"Defensively it was a great game and when you get lead like we did, it makes things a lot easier too," Richard said.

Game Notes

Upton has reached base safely in 18 straight home games ... The Diamondbacks have lost nine of their last 13 home contests ... San Diego shortstop Everth Cabrera was a perfect 24-for-24 in stolen bases this season, but was thrown out trying to swipe second in the third inning.