PHOENIX -- For the last few years, Merrill Kelly has been one of the National League’s most consistent pitchers, and the bad news for the rest of the league is that the D-backs right-hander may finally have mastered a slider.

Kelly used his slider as part of a six-pitch mix in his season debut, easily handling the Rockies across 6 2/3 innings as the D-backs won for the second straight night, this one by a 7-3 margin on a celebratory Friday evening at Chase Field.

The D-backs received their 2023 NL championship rings in a pregame ceremony, and manager Torey Lovullo was concerned about a possible let down in emotion come game time.

Lovullo’s fears were put to rest early as Lourdes Gurriel Jr. and Christian Walker hit back-to-back, two-out homers in the first inning to spot Kelly an early 2-0 lead.

Outside of a solo homer to Elias Díaz, Kelly was in complete control, limiting the Rockies to three hits while striking out eight and not walking a batter.

“He was making pitches,” Lovullo said of Kelly. “He did a great job. And the Rockies are aggressive and I think he just was pulling the string and changing speeds front to back and it was very effective.”

The slider has always been a part of Kelly’s arsenal, though his changeup is his signature pitch. This offseason, he made a point of working on the slider to make that breaking ball as effective as some of his other offerings.

As Spring Training went along, Kelly felt better and better about the slider. On Friday, he threw 14 of them out of his 79 pitches, the second-most sliders he's thrown in a single game in his Major League career. He got two called strikes on the pitch, and of the five sliders that Rockies batters swung at, they missed four times.

“Definitely the biggest takeaway, I think, for me was the slider today,” Kelly said. “That was obviously the first real live action -- it's hard to kind of compare it to spring just because the adrenaline and the speed is of the game is a little bit different than what it is during the regular season. But overall, the slider definitely jumped out as it seems like it's shown itself as a useful pitch.”

Kelly worked on the shape and look of the slider during the offseason to differentiate it from his cutter. It figures that opponents will see more of them going forward.

“If it continues to show the shape and the location that it did tonight, if that continues, then I definitely think it can be another weapon in the arsenal, for sure,” Kelly said.

It was Kelly’s 13th career start against the Rockies, so they knew what they were up against.

“No surprises there,” Colorado manager Bud Black said. “We've seen enough of him to know you know what his stuff does.”

About the only question after the D-backs blew the game open with a four-run sixth, thanks in part to a three-run homer by Alek Thomas, was how deep into the game Kelly would pitch.

After a 19-pitch first inning, Kelly was incredibly efficient with his pitches, needing just 50 to get through the next five innings.

With Kelly at 69 pitches through six, Lovullo faced a decision. During the spring, Kelly hadn't pitched more than 3 2/3 innings in any outing, so the manager had to ask himself whether he wanted to push his starter into the seventh.

In the end, Lovullo decided to let Kelly start the seventh, then pulled him at 79 pitches after he retired the first two batters of the inning.

“I was OK with coming out right there,” Kelly said.

The D-backs were certainly more than OK with the performance.