When the Jazz overcame a slow start and a double-digit deficit in the first quarter, it was impressive. When they did it all over again in the fourth quarter, it decided the game.

In the end, no one in attendance at Vivint Smart Home Arena on Saturday night cared that the Bucks were missing their starting backcourt, or on the second half of a back-to-back.

All that mattered was that Donovan Mitchell hit big shot after big shot down the stretch to score a career-high 46 points and outduel Giannis Antetokounmpo, as the Jazz rallied from a 17-point fourth-quarter deficit and knocked off the team with the best record in the NBA, 115-111.

Derrick Favors, who played the key minutes late over a struggling Rudy Gobert, added 23 points, 18 rebounds, and three blocks — and drained a key pair of free throws late that helped seal the deal.

“It’s just understanding that we’ve got nothing to lose when we’re down 17,” said Mitchell, who hit 15 of 32 shots, including 5 of 10 from deep. “You just fight, and take certain risks that maybe you don’t take when you’re up 17. We made the right plays, and we got stops. That’s really where it started.”

The Jazz won their fourth straight game to improve to 36-26 on the season.

With Eric Bledsoe (back) and Malcom Brogdon (right foot) both sitting out, Milwaukee went with a starting lineup that featured four players standing 6-foot-10 or taller; All-Star Khris Middleton, at 6-8, was the shortest Bucks player on the court at the opening tip.

Milwaukee’s length proved an immediate impediment, as the team raced out to an 11-0 lead, and wound up blocking seven shots in the game’s first six minutes (including six by center Brook Lopez).

JAZZ 115, BUCKS 111

• Donovan Mitchell totals 46 points and six assists, out-dueling Giannis Antetokounmpo down the stretch as Utah rallies from a 17-point fourth-quarter deficit.
• Derrick Favors, who played late in place of the struggling Rudy Gobert, adds 23 points, 18 rebounds, and three blocks.
• The win is the fourth straight for Utah, which improves to 36-26 on the season.

Still, that proved to be a relatively minor blip.

Once the Jazz switched to a more defensive-oriented lineup, with Royce O’Neale hounding Antetokounmpo, Utah swung the momentum and took control.

They closed the opening quarter on a 15-6 run, and when Favors started dominating down low on both ends, including a monstrous dunk over Ersan Ilyasova — “Derrick Favors had a beyond-outstanding effort tonight,” said coach Quin Snyder — and when his teammates on the perimeter started draining shots from deep, Utah led by as many as 13 points.

They could not sustain it, though.

Coming out of halftime with Jae Crowder starting in place of Favors, Milwaukee got off to an 11-4 run to tie the game again.

The Bucks led by five going into the fourth, and expanded their advantage to 90-73 with about 10 minutes to go, and it appeared as though the early rally would go for naught.

Except the Jazz weren’t done yet. They got started getting stops, and scored three straight buckets, and a 7-0 run made it a 10-point deficit less than two minutes later.

“We kept competing. It starts on the defensive end, and kind of having the will to continue to compete, regardless of the score or the situation,” said Snyder. “When you do that, it doesn’t always work out, but you give yourself a chance.”

The Jazz eventually tied it up at 95, and the teams took turns trading big shots down the stretch.

Mitchell nailed a couple of deep 3-pointers, and, after being double-teamed, found Favors down low, and the big man crucially converted a pair of free throws.

Mitchell called Favors “the MVP of the game.”

Gobert, who totaled just five points and nine rebounds, struggled to contain Antetokounmpo in their matchup, and was a minus-36 overall plus/minus, was even more praiseworthy of his fellow big man.

“I just got my ass kicked. I missed seven free throws. I just wasn’t good tonight. Props to coach for putting me on the bench and putting in Fav, who had a great game,” said Gobert. “… I’m just happy for him. It’s not always easy playing behind me, and sometimes you wanna finish the games, and usually he doesn’t; and playing the way he plays, whether it’s in Denver or here tonight, it’s unbelievable.”

Antetokounmpo finished with 43 points, 14 rebounds, eight assists, and two steals, but went just 11 of 19 at the line.

It was quite a lot. But against these Jazz, on this night, still not quite enough.

““We came out and played hard. Milwaukee is a good team. I know they were coming off of a back-to-back, but they have a lot of good players out there, so we just stuck together as a team,” said Favors. “We got down, but like I said, we stuck together and played hard.”