Defending champion Carlos Alcaraz handed Australian Open winner Jannik Sinner his first defeat of 2024 to return to the Indian Wells ATP Masters final on Saturday, beating the Italian 1-6, 6-3, 6-2.

The victory ended Sinner's 19-match winning streak, including a 16-0 start to the year, and insures Alcaraz will remain No. 2 in the world rankings next week.

In Sunday's final, he will face either fourth-seeded Russian Daniil Medvedev or American Tommy Paul with a chance to become the first repeat Indian Wells ATP champion since Novak Djokovic won three straight titles from 2014-2016.

A match disrupted by an early three-hour rain delay proved worth the wait, the pulsating rallies thrilling the Stadium Court crowd.

"Matches with Jannik are always special," Alcaraz said. "I always demand the highest level from myself against him and it's the same for him.

"We know we have to play at our highest level to win. We have put magic on the court, unbelievable points and for the crowd it is also wonderful."

Sinner quickly seized the initiative when play resumed, using his depth and accuracy to win four straight games to pocket the first set.

He saved the only break point he faced, and gained the insurance break for a 5-1 lead, pouncing on a short ball for a stinging cross-court passing winner on break point.

Alcaraz responded in the second set with a savvy change of style, backing up to give himself more time on the returns and gradually working his way into the match.

He broke Sinner with a deep volley winner for a 3-1 lead and held for 4-1 in a game that had fans on their feet cheering a thrilling rally at the net.

Sinner had opportunities, but was unable to convert after giving himself a break chance in the seventh game with a blistering service return.

Alcaraz saved another break chance with an impossible backhand winner down the line and sealed the set with a drop-shot winner.

- Mentally strong -

"I stayed strong mentally," Alcaraz said. "I think that's a really important part in this game.

"This kind of match, a set down playing against someone that's playing an unbelievable game -- I'm really happy with the things I've done.

"I changed my style a little bit, I changed my game a little bit, and I think it worked very, very well."

A few errant forehands from Sinner gave Alcaraz an opening in the third game of the final set and he gained the break when he came out on top with a high backhand volley to end another scrambling rally.

Sinner, who had dived to get a ball back, came up shaking out his right arm.

He suddenly seemed powerless to stop Alcaraz, who won five straight games, eventually clinching the match with a forehand winner on his third match point.

"(I'm) really, really happy to beat Jannik and obviously being in the final again," said Alcaraz, who is chasing his first title since his Wimbledon triumph last July.

It was the second straight year that Alcaraz stopped Sinner in the Indian Wells semi-finals.

Sinner had won both their meetings since and rode a 19-match winning streak into the contest. His 16-0 start to 2024 included his maiden Grand Slam title in Australia and a victory at Rotterdam last month.