PHOENIX -- Rubby De La Rosa hasn't had any success against his former team this season.
De La Rosa was roughed up for six runs and nine hits in two-plus innings by Los Angeles in the Arizona Diamondbacks' 9-5 loss to the Dodgers on Saturday night.
"I couldn't get my pitches down," De La Rosa said. "I don't know what happens against that team. I try to do the best I can to beat these guys."
De La Rosa (12-8) lasted even shorter than his two five-inning losses in which he allowed a combined 14 runs against the Dodgers earlier this season. He had another start in which he gave up two runs and six hits in 5 2/3 innings, but got a no-decision in a Dodgers win.
Corey Seager went 4 for 4 with a home run and Joc Pederson, Adrian Gonzalez and Carl Crawford also homered in this game for NL West-leading Los Angeles.
Diamondbacks manager Chip Hale said De La Rosa struggled with his location.
"He just has a hard time against this club right now. He'll have to get over that," Hale said. "They hit the ball hard."
Seager got help from a Diamondbacks fan who reached over the padding down the left-field line in the fifth inning to take a seemingly catchable foul ball away from David Peralta and Jake Lamb. Seager then homered in the same at-bat and another fan returned the ball to him.
Seager said he owed the first fan a thank you, too. Peralta was far less pleased.
"I was hustling all the way, trying to make the play," Peralta said. "I was under the ball and the fan just put his glove over mine. I got (mad). Then you see what happened, the next pitch he hit a home run."
Hale, in retrospect, wished he'd have asked for replay on the foul ball to check for fan interference.
"That was probably my mistake. I should have gone out," Hale said. "That's a challengeable play. We had the video."
J.P. Howell (6-1), the first of seven Dodgers relievers, got the last out in Arizona's three-run fourth to pick up the win.
Crawford began the game with his ninth career leadoff home run, a line drive just over the right-field fence. Then Chase Utley singled, took third on a two-out single by Andre Ethier and scored on Seager's soft ground ball to second base that Chris Owings juggled for a hit.
That gave the Dodgers a 2-0 lead in the first inning, and they went ahead 7-0 in the third on Gonzalez's leadoff home run, Ethier's run-scoring double, an RBI single for Seager and Pederson's two-run blast.
The Diamondbacks rallied for three runs in the bottom of the fourth and loaded the bases with two out, after Peter O'Brien's pinch RBI single and sacrifice flies for Nick Ahmed and Ender Inciarte.
Mike Bolsinger had thrown a wild pitch earlier in the inning to put runners in scoring position. He was replaced by Howell after an intentional walk to Paul Goldschmidt, and Howell got Peralta to fly out to shallow left field to end the threat.
Seager made it 8-3 with his home run, and Inciarte cut the lead to 8-4 in the sixth with a single to drive in A.J. Pollock.
Peralta's 15th home run of the season came in the seventh and Alex Guerrero added an RBI double in the ninth.
O'Nora joined the umpiring crew for the series in time for Saturday's game and worked home plate, with Jim Wolf out after being struck in the mask by a foul ball during the second inning on Friday night.
The Diamondbacks' regular-season finale on Oct. 4 against the Houston Astros has been changed from a 1:10 p.m. start time to 12:10 p.m, local time.
Dodgers: Zack Greinke (16-3, 1.68 ERA) is 8-2 in 13 road starts this season. He is 6-3 with a 3.62 ERA against Arizona in his career (13 starts), including a 5-2 mark at Chase Field.
Diamondbacks: LHP Patrick Corbin is 2-0 in his last three starts and 3-2 with a 3.82 ERA in six career starts against the Dodgers.
