Carlos Alcaraz made history on Sunday, defeating Casper Ruud in the final of the men's US Open to claim his first Grand Slam title and become the new world number one.
As the dust settles on the season's fourth and final Grand Slam event, here is a look at five of the big storylines from the men's hard-court tournament in New York.
There is no place better to start than with young Alcaraz's historic title triumph at Flushing Meadows.
Having long been considered the next big thing in men's tennis, Alcaraz lived up to the hype with a 6-4 2-6 7-6 (7-1) 6-3 victory over Ruud in his first ever major final and, in winning that match, the 19-year-old became the youngest men's Grand Slam champion since Rafael Nadal won the French Open in 2005.
The final in New York was also billed as a battle for the world number-one spot with the winner set to hit the summit of the ATP rankings.
With his win, Alcaraz jumped ahead of Daniil Medvedev into top spot and is the first teenager to occupy that position since the ATP rankings began.
It was a valiant final performance from the Spaniard, who saved two set points in the third, denying Ruud the chance to edge in front, and his US Open triumph feels like the start of something big.
He is 7/2 to win the next Grand Slam event - the 2023 Australian Open - and is also 7/2 to defend his US Open title next year.
Alcaraz has been on the radar of tennis fans for some time now but Norwegian starlet Ruud has only just started to make a breakthrough on the ATP Tour and can draw plenty of confidence from his run in New York.
Ruud also made the French Open final earlier in the year, where he was outclassed by clay-court specialist Nadal, but he should learn a lot from both defeats.
He had been a 65-1 outsider to win the US Open at the start of the tournament but defied expectations and it feels like only a matter of time before he will be celebrating a maiden Grand Slam success.
Coming into the season's final major, Ruud had also put together a run to the semi-finals of the ATP Montreal, suggesting he is a fan of the hard courts, and he can be backed at 16/1 to go one better and win the US Open next year.
But he has shown he can excel on all surfaces and is worth keeping an eye on at the end-of-season ATP Finals.
Having been unable to play at Wimbledon, Medvedev's full focus in the last few months would have been on going the distance at the US Open but, remarkably, the Russian did not even make the quarter-finals.
It caps off a frustrating season for Medvedev, who lost in the final of the Australian Open at the start of the year and could only make the fourth round of the French Open.
He won his first three matches in New York in straight sets but came unstuck at the first sight of trouble against fiery Nick Kyrgios in the last 16.
Following that win over Medvedev, many expected Kyrgios to make the most of his experience and take the title at the US Open.
Roger Federer and Novak Djokovic were absent and Nadal had been knocked out, paving the way for Kyrgios to win his first major title after finishing runner-up at Wimbledon earlier in the summer.
But emotions once again got the better of Kyrgios, who lost in five sets to Karen Khachanov, a player four places below him in the seedings.
Despite that, the Australian can reflect on a great season in which he came closer than ever before to landing a Grand Slam title and, with the support of a home crowd behind him at the start of next year, he could be worth a look at 7/1 to win the 2023 Australian Open.
Nadal did not look at his sharpest in the early rounds of the US Open, falling a set down in matches with unseeded players Rinky Hijikata and Fabio Fognini.
And although the Spaniard responded with a straight-sets dismantling of Richard Gasquet in the third round, his tournament came to an end in the following round against American Frances Tiafoe.
It was an unexpected result but in hindsight Nadal's match practice had been limited going into the hard-court major and there were concerns over the Spaniard's fitness.
Nadal started the year with triumphs at the Australian Open and French Open to go top of the all-time men's Grand Slam title standings but, following his struggles at the US Open, he could be set to take some time out from the sport as he goes in search of a record-extending 23rd major title.