PHOENIX -- Arizona Diamondbacks catcher Chris Iannetta had two questions when he learned he would be hitting second against the San Diego Padres on Thursday.

"I asked if it was a typo," Iannetta said.

"Then I asked if we were trying, joking around."

No joke. Iannetta homered, doubled twice and drove in a career-high seven runs when the D-backs completed a three-game sweep with a 15-4 victory over the Padres at Chase Field.

Iannetta, hitting second for the first time this season, hit a two-run homer off Clayton Richard for a 4-3 lead in the fifth inning before hitting a bases-loaded double in a six-run sixth and a two-run double in a four-run eighth.

"It was exciting," Iannetta said. "It was fun. These are the days you play baseball for, the chance to contribute and you have fun while doing it. I feel like a kid again."

Daniel Descalso had two hits, including a homer, and drove in two runs as the Diamondbacks (37-25) improved to a major league-best 24-8 at home, the best home start in franchise history.

Paul Goldschmidt, Chris Owings and Nick Ahmed had two hits apiece for the Diamondbacks, who outscored the Padres 32-9 in the series. Their 15 runs were a season high, and they scored their first 10 with two outs and no one on in an inning.

"Pretty offensive day," said Arizona manager Tony Lovullo, who added that he had been toying with the idea of putting Iannetta second for a few day.

"The game turned around in a hurry. I was really proud of what we did against a pitcher that has typically thrown very well against us. Our guys had a really good approach. Obviously the day was highlighted by Chris Iannetta."

The D-backs have used four No. 2 hitters in front of Goldschmidt in an attempt to maximize production against left-handed starters this season.

"To hit in front of one of the best hitters in the game, you know you are going to see some pitches to hit," said Iannetta, whose previous career RBI high was six.

"It's a boost of confidence to know all you have to do is pick one out. They don't want to face him. They would rather face me."

Wil Myers, Hunter Renfroe and Jose Pirela had two hits apiece for San Diego (23-38), which has lost five in a row after a five-game winning streak.

Arizona left-hander Patrick Corbin (5-6) gave up eight hits and three runs in 5 2/3 innings, his second victory over the Padres in three starts this season. He struck out eight and walked three.

Richard gave up six hits and four runs in five innings for the Padres, who led 2-0 and 3-2 before Iannetta took over.

Richard (4-7) has made four starts against Arizona this season, winning the two at home and losing the two at Chase Field. He gave up two runs in 15 2/3 innings at Petco Park and 10 runs in 8 2/3 innings at Chase Field.

"Through the game, we just didn't finish innings," Padres manager Andy Green said. "It's just not good baseball, I don't think there's really another way to describe it. You give some credit to their guys. Those guys compete to the last out of every single inning. They make you earn your outs. They don't get outside the strike zone, they don't chase a lot. They don't give you easy outs."

San Diego took a 2-0 lead on two walks and three singles in the first inning, with Austin Hedges' two-run, bases-loading single making it 2-0.

The Diamondbacks tied it in the bottom of the first after Goldschmidt singled with two outs. Owings doubled in one run and Descalso singled in the second.

Myers singled and scored on Renfroe's double to open the third for a 3-2 Padres lead.

Gregor Blanco had a bunt single down the third base line with two outs in the fifth before Iannetta homered off Richard to make it 4-3.

With two outs in the sixth inning, Brandon Drury was hit by a pitch, Jake Lamb walked and Ahmed hit an infield single to load the bases before David Peralta's pinch-single made it 6-3. Iannetta followed with his double to the fence in right-center field for a 9-3 lead.

Iannetta's two-run double started a four-run eighth off Brandon Maurer, who did not retire any of the five batters he faced.

NOTES: Padres SS Erick Aybar got the final three outs in his second relief appearance of the season, both against the Diamondbacks. He retired the only batter he faced in one-third of an inning April 18. ... Arizona RHP Zack Greinke was placed on paternity leave Thursday to be with his wife, Emily, for the birth of their second child. His next scheduled start is Tuesday. RHP Silvino Bracho was recalled from Triple-A Reno for his fourth stint with the D-backs this season to fill the roster opening. ... San Diego RHP Miguel Diaz is to get his first major league start Saturday at home against Kansas City, replacing RHP Jarred Cosart (elbow).