PHOENIX -- For the second straight game, the D-backs utilized the energy emanating from the seventh-inning stretch to spur a go-ahead rally.

Pavin Smith and Daulton Varsho hit booming back-to-back solo shots to lead off the seventh, paving the way for a 6-4 D-backs victory over the Pirates on Wednesday afternoon at Chase Field to complete the three-game sweep. The win is their fourth in a row, marking the club’s first four-game winning streak since April 18-22.

“Me and [Varsho] have hit back to back for three or four years in the Minor Leagues, and we never got to hit back-to-back home runs,” Smith said. “Finally, today, we got to do it. So it was really cool.”

Leading off the seventh, Smith’s homer was of the no-doubt variety. Garnering a 1.000 xBA, Smith deposited a center-cut 1-0 changeup from Pirates reliever Duane Underwood Jr. far beyond the right-field fence; the blast traveled a Statcast-projected 432 feet the sixth-longest home run of his career.

“I was looking for a fastball,” Smith said. “He threw me a first-pitch curveball … and it was a ball. And then he kind of just threw a changeup up. I was able to kind of pause and see it and stay behind it.

“It was kind of one of those where I was like, ‘I’m pretty sure that might have been a changeup, but it could have been a fastball, I don’t even know.’ But when I looked up at the [scoreboard], it was a changeup. I was like, ‘All right, nice.’”

Varsho followed with a blast, producing a 104 mph exit velocity, per Statcast. After a recent spate of being scuffling against southpaws, the left-handed-swinging Varsho was able to hone in against a righty and connect -- loudly.

“When you face lefties consistently, usually it locks [you] in and it can help your right-handed approach a little bit, because it makes you stay on the baseball a little bit better,” Varsho said.

Varsho finished 2-for-4, giving him back-to-back multihit games for the first time this season. After playing a pivotal role in Tuesday’s eight-run seventh, he was back in the thick of the action vs. the Bucs, also recording seven putouts in center field, setting an outfield career high.

“I’m not missing a couple of pitches that I was missing a couple of weeks ago,” Varsho said. “Now I’m just trusting everything I do in the cage and it’s kind of translating a little bit right now. I got to keep doing it. I got to keep putting in that work so that I can keep [getting] those results in a game.”

Manager Torey Lovullo was complimentary of the “barrel awareness” shown by the lefty-swinging duo.

“They’re putting themselves in a good hitting position and not missing the pitch they’re looking for,” Lovullo said. “They’re working hard for it, especially Daulton, and [it] helped us win a baseball [game] and that’s the bottom line.”

As of late, the D-backs have seen nearly all sections of their lineup execute and play well.

The sweep was the first since the D-backs ran roughshod on Reds pitching at Great American Ball Park in April, when they combined for 27 runs.

While the offensive output wasn’t nearly as gaudy this time around, Arizona has scored at least six runs in three of its last four games.

Coming out of the All-Star break and hitting the ground running, Smith has been an integral cog in the club’s offensive production. He has enjoyed the first three-game stretch of his career in which he has plated a run in each outing.

“I feel good,” Smith said. “I feel rested after the All-Star break and had a good approach coming into each one of these games. I feel like I executed pretty well.”