INDIAN WELLS (AFP) — Defending champion Carlos Alcaraz will have to find a way past "the best tennis player in the world right now" when he takes on Jannik Sinner in the semifinals of the Indian Wells Masters on Saturday.

The 20-year-old Spaniard, already a two-time Grand Slam champion, is chasing his first title since he vanquished Novak Djokovic at Wimbledon last July.

Sinner, meanwhile, is on the ascendant. The 22-year-old Italian is riding a 19-match winning streak that stretches back through last year's Davis Cup finals.

His perfect 16-0 record in 2024 includes a maiden Grand Slam title at the Australian Open and the title at Rotterdam last month.

Not only can he end Alcaraz's hopes of a title defense, with a victory on Saturday, Sinner would be assured of claiming the world No. 2 ranking for the first time come Monday.

"Honestly, I don't know how I'm going to approach the match," said Alcaraz after beating Alexander Zverev 6-3, 6-1 in the quarterfinals.

"He's the best tennis player in the world right now, without a doubt. He's playing unbelievable. No losses this year."

"So, it's going to be a really difficult match. It's going to be a big challenge for me to see what my level is facing him."

Alcaraz, who retired from his opening match in Rio de Janeiro in February with a sprained ankle, has gone from strength to strength in Indian Wells, reaching the semis with the loss of just one set.

Against Zverev — in a quarterfinal disrupted by a swarm of bees — Alcaraz didn't face a break point.

Sinner, who fell to Alcaraz in last year's Indian Wells semis before beating him at the same stage in Miami, has been just as impressive in reaching the last four without dropping a set.

"Carlos, it's always fun to play with him," said Sinner, who has won their last two encounters to lead their career head-to-head 4-3.