Carlos Alcaraz ensures a new US Open champion will be crowned Sunday

Carlos Alcaraz

All eight men left in the US Open draw are chasing their first Grand Slam title win with Carlos Alcaraz retaining hopes of becoming the new World No 1 to cap an incredible breakout year.

Alcaraz battled past Marin Cilic in a five-set epic late on Monday night 6-4, 3-6, 6-4, 4-6, 6-3 with the match eventually concluding after 02:00 local time.

It didn’t seem like a soul had left Arthur Ashe Stadium despite the late finish with the crowd roaring on the combatants.

Alcaraz concedes that he doesn’t really know how he pulled the result out of the hat.

“Honestly, I have no idea,” Alcaraz said.

“It was pretty, pretty tough at the beginning of the fifth set [being a] break down. But Marin was playing unbelievable. I believe in myself all the time. Of course the support today in Arthur Ashe [Stadium] was crazy. Without you guys, it wouldn’t be possible to win this match tonight, so thank you very much for the support tonight, thank you.

“I would say 100 per cent of the energy I put in the fifth set was thanks to you. It was unbelievable.”

After the fourth round exits of Daniil Medvedev and Rafael Nadal, the World No 4 is the highest-ranked player in the field and can also clinch a place in the ATP Tour finals this week.

Alcaraz appeared to be wavering as he slipped from a 2-1 set lead to see parity restored and then go a break down in the final set before powering back.

“After a fourth set [when] I had a lot of opportunities… it was tough for me to come back in the fifth set, to stay strong mentally,” Alcaraz said. “But as I said, the energy that I received today made me win.”

Alcaraz is far from a sure thing in the US Open as he goes on to face something of a bogey player in the last eight.

Young Italian Jannik Sinner is the man slated to meet Alcaraz and comes into the match having beaten the Spaniard in their last two meetings.

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Sinner won when the pair met at Wimbledon earlier this season ending a career-best run for Alcaraz at the time.

Then before the tour made its Atlantic crossing, Sinner overcame Alcaraz to win the title in Umag.

“I played a couple of times against him. He’s a great player, a really, really tough one,” said Alcaraz, who trails their ATP Head2Head series 1-2. “I lost twice in the past two months, so I will have to be ready for this battle against Jannik.”

Alcaraz is the youngest man to reach back-to-back US Open quarter-finals in the open era thanks to his victory over former champion Cilic.

The race for the World No 1 ranking also includes World No 5 Casper Ruud who can take the top spot if he either beats Alcaraz in the final or reaches the championship match should the Spanish teen fall earlier.