Turin erupts as a Jannik Sinner backhand winner kisses the tramline.

However, Carlos Alcaraz responds with a body serve followed by a well-executed serve and volley to hold to 15.

Still no sign of a break point.

After back-to-back deuce games, Jannik Sinner holds to 15.

It's not as comfortable as the scoreline suggests - both players have produced a number of uncharacteristic groundstroke errors - but he seals the hold in style, dragging Carlos Alcaraz across the baseline before sending down a powerful forehand winner.

What was I saying about Jannik Sinner and longer rallies? Don't listen to me. After trading several cross-court forehands, Alcaraz pummels a backhand down the line for advantage.

Sinner then sends a forehand long to secure the hold for Alcaraz.

Jannik Sinner is just starting to get the edge in the lengthier rallies. He clips the baseline a couple of times for 15-all before Carlos Alcaraz fires a forehand long.

The Spaniard retakes the lead for 40-30 but fires a routine forehand into the net.

Jannik Sinner maintains his composure after the delay, coming into the net to bury a volley before firing down an unreturned serve to hold.

Play resumes after an 11-minute delay.

It's deuce in the fourth game.

Image source, Getty Images

Both players have been in conversation with the umpire as the final remains paused in Turin.

It's been a comfortable start from Carlos Alcaraz, who has only dropped one point in his opening two service games. And the world number one has a golden opportunity for an early break, with the fourth game of the opening set at deuce.

Well, this has been a bit messy from Jannik Sinner.

A second ace of the day - down the T - brings up 30-0 but a couple of forehand errors see him pegged back to 30-all.

He's then grateful to a helpful net chord after finding himself on the backfoot in a baseline battle but a double fault brings up deuce.

Play is paused due to an incident in the crowd.

Oh ho! Carlos Alcaraz is up for this. Chasing back across the baseline, he hooks his forehand down the line and just out of Jannik Sinner's reach.

Alcaraz roars. Sinner applauds on his racquet strings. 30-0.

Another comfortable hold.

Sinner pings down an ace for 40-0 and gives a small smile as he prepares for his next serve.

He's yet to lose a service game in Turin this week.

Well, it's evident from the off that the Turin crowd will cheer every point which goes Jannik Sinner's way as a Carlos Alcaraz forehand into the tramlines receives enthusiastic applause.

However, it's a routine hold to 15 for the world number one.

It’s time! Rome, Roland Garros, Wimbledon, Cincinnati, Flushing Meadows, and now Turin.

The world number one vs the world number two.

But who will have the final word in 2025?

*denotes next server

Image source, Getty Images

Britain's Henry Patten is an ATP Finals champion - capping a remarkable week in his life.

He and Finnish partner Harri Heliovaara beat the all-British team of Joe Salisbury and Neal Skupski earlier on Sunday, adding to the Australian Open title they won at the start of the year and their 2024 Wimbledon title.

Patten got engaged to girlfriend Ellie last Sunday and made it a doubly joyful trip to Turin with his success alongside veteran Heliovaara.

You can read more about their achievement here: Patten's partners make it dream week for him at ATP Finals

Jannik Sinner wins the coin toss and elects to receive.

While the players warm up, here's a reminder of what happened in today's doubles final...

Here they come!

Defending champion Jannik Sinner is roared by his home crowd. World number one Carlos Alcaraz enters to muted applause.

The players are waiting in the wings of Turin's Inalpi Arena.

Carlos Alcaraz, cool as a cucumber, is juggling a couple of tennis balls while jogging on the spot. Is there anything he can't do?

But before they come out, the arena is lit up in green, white, and red for the Italian anthem.

Laura Robson
Former British number one on Sky Sports

He is an absolute superstar here and this crowd has been ready to go since gates opened. I think it's going to be like a Davis Cup atmosphere.

Carlos was the first one to say that after his semi-final and I can't argue with that. It's going to be one-sided. He's got a small contingent of fans - a couple of Spanish flags I've seen.

Image source, Getty Images

This is new territory for Carlos Alcaraz. After being forced to pull out due to injury after qualifying in 2022, he was knocked out in the semi-finals in 2023 and the group stage in 2024.

Victory over Sinner would make him only the third Spanish winner of the men's singles, joining Alex Corretja (1998) and Manuel Orantes (1976).

However, he is well aware that he will not only have to overcome Sinner but also a partisan Italian crowd.

"I know I have to play my plan A if I want to win the tournament. We're both going to raise our levels," he said following his semi-final win.

"The whole stadium is going to be supporting him, which I have to be prepared for. I hope that at least three or four people are cheering for me."

Sinner, for his part, said of the final: "These are matches I look forward to. Also to see for me where my level really is, but in the same time it's great before the off-season to have this match-up."

Image source, Getty Images

Sinner, who turned 24 in August, is the youngest man to reach three ATP Finals title matches since Lleyton Hewitt achieved the feat as a 23-year-old - getting to the showpiece in 2001, 2002 and 2004.

Tim Henman, who reached the semi-finals of this event in 1998, allowed himself to imagine a scenario where there was even more on the line than there already is today.

If number one in the rankings was also up for grabs, it would have made the match all the more seismic as a sporting occasion.

Had Sinner been able to take his big chance against Alcaraz at Roland Garros, where he let three championship points slide by in the fourth set, the top ranking might well have been an added prize in this tour season climax.

As it turned out, Alcaraz entered Sunday's match with a 4-1 season head-to-head lead over Sinner.

Speaking on Sky Sports, Henman said: "I think perhaps the most critical point was that French Open final because Sinner had the three match points.

"If you reverse that result and see what it does to the ranking points, it could have put a very different angle on this week at the end of the year."