The Dodgers didn’t land one before the Trade Deadline, so they have the month of September to find a No. 3 starter from their existing rotation for the best-of-three first round of the postseason.

Tryouts began on Tuesday night, when Julio Urías rebounded with the kind of start he needed in a 6-3 win over the D-backs at Dodger Stadium, with Chris Taylor replacing the scratched Cody Bellinger and driving in four runs.

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Granted, the last-place D-backs didn’t exactly provide an acid test the day after they unloaded their best veterans at the Deadline. But a Major League win counts no matter the opponent and Urías took a positive step, allowing one run in six innings, especially coming off a four-run, four-inning start in San Francisco. He has three wins this year, two of them against Arizona, and he even avoided the first-inning trouble that had become a bad habit.

“Very impressed,” said manager Dave Roberts. “And that’s even saying for the first five innings, he didn’t have a feel for the changeup. That speaks to his command of the slider or slurve or whatever he has and the fastball. It played really well tonight.”

Urías, who will pitch Sunday on regular rest for the first time this year, struck out five without a walk. By contrast, Dodgers batters drew a season-high eight walks.

Barring injury, Roberts will be picking from Urías, Dustin May and Tony Gonsolin to slide between Clayton Kershaw and Walker Buehler come October. As electric as May and Gonsolin have been at times, Urías actually is the veteran of the bunch in both regular-season and postseason experience.

“He just hasn’t been consistent with his delivery, and tonight he sort of put it all together,” said Roberts. “Something we knew was obviously in there, we’ve seen it many times before. But for him to spit out a good one and hopefully gain some traction with his next one Sunday. We’re going to need him to pitch some big innings.”

Urías was as efficient as he was effective, requiring no more than 15 pitches to complete any inning.

“[Pitching coaches Mark Prior and Connor McGuiness] worked really hard in the ‘pen dialing in that slider, and tonight, for me, the slider was the difference,” said Roberts. “[Urías ] shortened it and to strike it and then pitch off that with the fastball and getting ahead with strike one.”

As part of management’s stealth youth movement, veteran starters Hyun Jin Ryu, Kenta Maeda and Rich Hill left the rotation because the Dodgers were counting on the 24-year-old Urías, 22-year-old May and 26-year-old Gonsolin to take over.

With Urías, Roberts has been imploring him to be more aggressive and challenge hitters rather than nibble.

“With Julio, I think it’s more when he’s got the feel for his pitches and the delivery is synced up, he’s going to be good,” he said. “Just getting that mindset from pitch one to be aggressive is the messaging we talk to him about.”

Roberts said Urías should interpret the club’s inaction at the Trade Deadline as a vote of confidence in the pitchers already on the team.

“We’ve said from the beginning that we see Julio as a starter and this was his time, this season,” Roberts said. “I hope he knows that we, as an organization, have a lot of confidence in him. Today he really pitched like that, and there was no need for us to look for another starter.”