PHOENIX -- In the leadoff spot for the first time in his career, Arizona's Chris Herrmann reminded himself to watch a few pitches in his first at-bat. Five was just right.

Herrmann hit the sixth pitch he saw for a homer in the last of the first inning.

Daniel Descalso chipped in with three RBIs when the Diamondbacks extended the best start in franchise history with a 6-1 victory over the Philadelphia Phillies at Chase Field on Monday.

"To hit a home run my first leadoff appearance, that's pretty sweet," said reserve Herrmann, who has played left field and catcher this season.

"I know you are supposed to see a lot of pitches, so I did that part. I got a good pitch to hit. It was pretty cool. Probably one of my favorite home runs I've ever hit, because I'm not a leadoff hitter."

Herrmann's homer was his career-high seventh, and it gave the Diamondbacks (49-28) an early lift on on their 15 victory in 18 games. Arizona is three games ahead of the previous franchise record pace set by the Randy Johnson/Luis Gonzalez 2001 team.

With leadoff hitter A.J. Pollock on the disabled list and new leadoff hitter Gregor Blanco given a day off, Herrmann was the seventh player manager Torey Lovullo has used at the top spot.

"I felt on the very low side he was going to have quality at-bats and drive up pitch counts," Lovullo said. "The high side of it was, he drove the pitch out of the ballpark. That didn't surprise me at all. I thought he was going to be engaged."

Descalso had an RBI single in a two-run second inning and a two-run single in a three-run third as the Diamondbacks gave right-hander Zack Greinke a 6-1 lead.

Greinke (9-4) gave up one run and three hits in five innings but left after throwing 102 pitches.

"I was missing by a little bit and they weren't swinging at it," Greinke said. "I wasn't trying to miss by a little bit, but it was just happening. Sometimes they swing at that pitch, but today they weren't, having a more patient eye and I had a deeper pitch count because of it."

Left fielder Daniel Nava had two hits and drove in a run for the Phillies (24-51), who have lost three in a row and 16 of 19. The Phillies are a major league-worst 10-31 on the road.

After winning the series opener 6-1 on Friday, the Phillies scored three runs in the final three games of the wraparound series.

"You know the old saying, pitching and defense wins games," Phillies manager Pete Mackanin said. "But if you can't hit, you can't win a lot of games. It's hard to deal with. If it's not one thing, it's another."

After Herrmann gave the Diamondbacks a 1-0 lead with his seventh homer, Chris Owings opened the second inning with a double off Phillies starter Nick Pivetta (1-4) and Descalso singled to make it 2-0. Pivetta walked the next three, the walk to Herrmann forcing in another run.

David Peralta and Jake Lamb singled and Owings walked to open third inning before Descalso's two-run single made it 5-0. Rey Fuentes singled in the final run of the inning.

Greinke gave up singles to two of the first three batters he faced before retiring 12 in a row until the Phillies scored in the fifth inning.

Brock Stassi and reliever Adam Morgan walked before Nava's two-out single drove in Stassi. Freddy Galvis walked to load the bases but Greinke got Aaron Altherr to ground out to third base on a 3-2 slider to end the inning.

Pivetta gave up six runs on seven hits and five walks before leaving with two outs and the bases loaded in the third inning.

"I didn't really have much of a release point," Pivetta said. "I beat myself up. Let the team down."

NOTES: Arizona 1B Paul Goldschmidt did not play for the first time this season, the third game he has not started. Goldschmidt is the NL RBI leader with 65. ... Arizona IF/OF Daniel Descalso, who started at first base, had RBIs singles in three straight plate appearances, starting with this walkoff single in a 2-1, 11-inning victory Sunday. ... Philadelphia recalled RHP Ricardo Pinto from Triple-A Lehigh Valley on Monday when LHP Edubray Ramos was optioned to Lehigh Valley. ... Arizona 2B Chris Owings extended his hitting streak to a career-high 12 games with a second-inning double.