HOUSTON -- Pavin Smith homered in first three at-bats for his first multi-home run game and drove in a career-high eight runs, helping the Arizona Diamondbacks rout the Houston Astros 12-6 on Sunday night to end a three-game losing streak.

Smith became the second Diamondback with a three-homer game this season, with Eugenio Suarez doing it against Washington on July 30. J.D. Martinez set the Arizona record with four home runs at Los Angeles on Sept. 4, 2017.

"It was a great day for Pavin," Diamondbacks manager Torey Lovullo said. "Pavin can hit. We always feel comfortable with his at-bats, his ability to come in the lineup after not playing for a couple of days and be able to barrel up the baseball."

Smith fell an RBI shy of the Arizona record set by Erubiel Durazo in 2002. Chris Iannetta also had eight RBIs for the Diamondbacks in a 2017 game. Smith's previous high was six.

Arizona -- which scored at least 10 runs for a majors-best 18th time -- pulled within a half-game of San Diego for the National League's first wild card and increased its lead over New York and Atlanta to 1 games. Houston leads Seattle by 4 games in the AL West.

Smith's first home run of the night followed back-to-back singles to start the second inning and struck the foul pole in right. Arizona had increased the lead to 4-0 when Smith came up with the bases loaded in the third and sent a 2-2 fastball from Justin Verlander (3-6) into the Crawford Boxes for the third career grand slam.

"Just one of those nights where you're in a zone," Smith said. "Obviously, Justin's a great pitcher. I faced him before, and he's got great stuff, so once I was able to put a good swing the first at-bat it gave me confidence the rest of the game."

Verlander allowed eight runs on eight hits over three innings and failed to record a strikeout for just the third time in 381 career regular-season starts. He has a 9.68 ERA in four starts since returning from the injured list.

"Felt better, physically," Verlander said. "It seemed like they had a really good game plan, and saw some pitches really well in some surprising spots, so tip your cap."

With Verlander out of the game, Smith answered Alex Bregman's fourth-inning, two-run home run by starting the fifth with his seventh homer of the season, a solo shot off Kaleb Ort that left the bat at 112.1 mph. Smith wanted to hit a fourth home run, but he struck out and walked in his final two plate appearances.

"It's something that not many people have done, and I figure if you have the chance you might as well go for it," Smith said.

Suarez was 4-for-5 with his 26th homer, 2 RBIs and 4 runs.

Kevin Ginkel (8-3) got the last out in the fifth for the victory.

Chas McCormick and Yainer Diaz each had three hits for the Astros. McCormick is batting .409 in six games since being recalled from Triple-A.