Carlos Alcaraz came through a thriller against Taylor Fritz to move within one win of the year-end world number one ranking, and Lorenzo Musetti captivated the crowd at the ATP Finals in Turin.

Spanish top seed Alcaraz battled back to overcome American Fritz 6-7 (2-7) 7-5 6-3 in a high-quality two-hour and 48-minute contest.

But despite achieving back-to-back victories, Alcaraz must wait to confirm his place in the knockout stages after Musetti's stirring victory against Alex de Minaur.

Backed by passionate support, ninth seed Musetti produced a remarkable comeback from 5-3 down in the deciding set to prevail 7-5, 3-6, 7-5.

Alcaraz will seal the world number one ranking - and a place in the semi-finals - with victory over Musetti on Thursday.

Rival Jannik Sinner must defend his title and hope Alcaraz loses a group match and does not reach the final to claim the top ranking.

On whether achieving the year-end number one ranking played on his mind during his match, Alcaraz, 22, said: "It's really difficult not to think about the number one spot.

"At the beginning of the match, I thought a little bit about it. During the match, there were a lot of things to think about.

"The number one thought - I didn't think about it at all during the match."

Having contested six matches in the past seven days after his run to the Athens Open final, Musetti will be grateful for a rest after his two-hour and 48-minute epic.

Musetti, 23, said: "With a big heart and a big passion - I don't know from where - I started to play better.

"The support of the crowd was amazing, so I have to thank them all."

Musetti's match against De Minaur was paused for about eight minutes because of a medical emergency in the stands. Two spectators died from cardiac arrest at the tournament on Monday.

Alcaraz forced to dig deep by impressive Fritz

Sixth seed Fritz, the 2024 runner-up, matched Alcaraz for much of their absorbing meeting. But Alcaraz, as he so often does, just found another gear to turn the match around.

An opening four games lasting 30 minutes set the tone, with both players exchanging breaks in lengthy service games.

Fritz, who won the pair's most recent indoor meeting at the Laver Cup in September, missed two break points in the eighth game, but maintained pressure and seized control of the tie-break to deservedly claim a 70-minute first set.

Alcaraz earned a crucial hold of serve after an eighth deuce in a captivating 14-minute fifth game of the second set, pointing to his ear as he lapped up the crowd's appreciation after saving two break points.

Fritz overcame his first test of the second set to seal an important hold for 4-4 but he could not escape four games later when, seemingly from nowhere, a rare double fault contributed to a 0-40 deficit - and Alcaraz took his opportunity.

Fritz continued to go toe-to-toe with his opponent and ended the match with 75% first serves in, but Alcaraz took full advantage when his level eventually dipped.

Breaking for a 4-2 lead, Alcaraz sought to finish in style and landed a spectacular overhead backhand drop shot to reach a third match point on Fritz's serve.

Fritz rightfully received the adoration of the crowd for hanging in the contest, only for a free-flowing Alcaraz to serve out the match to love.

"It was tight. I felt I was struggling more than him," Alcaraz added.

"I was really relieved after the win because of everything I went through physically. I'm really happy that I found a way to come back and find his weaknesses."