SAN DIEGO -- There was a time a few weeks ago when it looked like Merrill Kelly was in danger of losing his spot in the D-backs’ rotation.

On Friday night at Petco Park, Kelly turned in his fourth straight outstanding start as the D-backs beat the Padres, 9-0, and the rookie right-hander is now making his case for the 2020 rotation.

The win was the third in the last four games for the D-backs, who are five games behind the Brewers for the second National League Wild Card spot with eight games left.

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Kelly (12-14) allowed just two hits over seven shutout innings to extend his scoreless innings streak to 15. Kelly also threw seven shutout innings in his last start against the Reds and has allowed only three runs over his last 27 innings, spanning his four September starts.

“I think he’s on that ride, on that wave, that a lot of players look for,” D-backs manager Torey Lovullo said. “He’s executing at a pretty high level. That’s in-game. I think the preparation, the game-planning, has been improving with each outing.”

Kelly has tweaked his mechanics just a bit, turning his body a little more when gathering himself during his windup, but the majority of his changes have come between his ears.

“I think really it just came down to -- a lot of it was mentality,” Kelly said. “Just being aggressive and not giving the hitters too much credit and not trying to nitpick and throw perfect pitches. Just having the confidence that I’m good enough as myself and don’t need to be any better than what I’m doing is kind of what it boils down to.”

And instead of waiting to work his way into a game, Kelly has focused on being ready to go from the game’s first pitch.

“It finally took until the last month and a half of the baseball season to get to that point where he’s walking off the mound in the bullpen and standing on the [game] mound throwing his first pitch as his best pitch,” Lovullo said. “I think there’s a lot to be said for that. The velocity has climbed a little bit, and it’s maintained. I don’t think he’s working into his outings. He’s ready to go from the first pitch on.”

Kelly, 30, pitched the past four years in Korea before signing a two-year, $5.5 million deal with the D-backs during the offseason. The contract includes a pair of club options for 2021 and 2022.

With one more start ahead this year, Kelly has put together a solid rookie season, compiling a 4.31 ERA and allowing 176 hits in 177 1/3 innings.

Those numbers would be even better were it not for a six-start stretch from July 23-Aug. 23 in which he had a 9.20 ERA.

“It’s been a roller-coaster, for sure,” Kelly said. “There’s definitely been some highs and lows, definitely some learning experiences -- which I feel like your first year in the big leagues, that’s partly what it’s about is learning as much as you can, not only about the hitters but about yourself. I think that I’ve done that this year. I’m happy where we are now.”

There will be competition next year for spots up and down the D-backs’ roster, and the rotation is no exception.

Luke Weaver and Taijuan Walker figure to be healthy, and the team added Zac Gallen and Mike Leake at the Trade Deadline. Robbie Ray is under control for one more season. There’s Kelly and also young pitchers such as Taylor Clarke and Alex Young, who have had their moments this year.

“Competition will be one of the better drivers of our future success,” general manager Mike Hazen said. “I feel like if one of the things we’re looking back on [is] we are going to have a lot more competition all over the field, I see that as a big picture positive sign for the organization.”