The 19-year-old is the youngest man to make a slam final since his fellow Spaniard Rafael Nadal won his maiden title at the French Open back in 2005.
Comparisons between the compatriots are inescapable and Alcaraz, who had battled for five sets beyond 2am in his previous two matches, showed Nadal-like powers of mental and physical endurance to recover and beat American Tiafoe 6-7 (6) 6-3 6-1 6-7 (5) 6-3.
It has been a breakthrough tournament for 24-year-old Tiafoe, who defeated Nadal for the biggest win of his career in the fourth round before becoming the first American man to make the last four in New York for 16 years and the first black American man since Arthur Ashe in 1972.
But it is third seed Alcaraz that will go forward to the final to take on Norway’s Ruud, with both men knowing victory would put them on top of the rankings – Alcaraz as the youngest man ever.
Here’s everything you need to know.
When is the US Open men’s final?
Casper Ruud vs Carlos Alcaraz will get underway from just after 9pm BST today, Sunday 11 September.
How can I watch the US Open men’s final?
The US Open will be shown live on Amazon Prime in the UK, with all matches from the tournament available to stream on Prime Video which is available on Smart TVs and the Prime Video app as well as online. If you’re not an Amazon Prime Video subscriber start a free 30-day trial here.
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