The final grand slam of the year is almost upon us as the world's best tennis players descend on Flushing Meadows in Queens, New York.
Last year's tournament saw Emma Raducanu emerge to end Britain's 44-year women's grand slam drought.
In the men's draw, a legend fell just short of making history when Novak Djokovic was denied a calendar Grand Slam by Daniil Medvedev.
Here's all you need to know about this year's fourth tennis major.
Is Novak Djokovic going to play?
Wimbledon champion and three-time US Open winner Djokovic was named as an entrant in the men's draw, but his unwillingness to be vaccinated against COVID-19 has once again come back to bite him.
The current advice from the US CDC (Centres for Disease Control and Prevention) states that if you're unvaccinated and a non-US citizen, you can't enter the country.
That's the reason Djokovic has been a conspicuous absentee from the US hardcourt season thus far.
It's also the reason why he's been forced to withdraw from the US Open — the second grand slam tournament he's missed this year after being deported from Australia and missing the Australian Open in January.
The US Open itself does not have a vaccination mandate in place for players, however, it says on its website "it will respect the US government's position regarding travel into the country for unvaccinated non-US citizens".
Also missing will be Roger Federer and Alexander Zverev, making for a very open draw, with Nadal up against reigning champion Medvedev and a host of other rising stars, such as Stefanos Tsitsipas, Carlos Alcaraz, Casper Ruud, Andrey Rublev and possibly even Nick Kyrgios all a chance to compete for their first grand slam singles title.
Is this Serena Williams's last US Open?
This US Open is more than likely to be Serena Williams's swan song as a professional player.
The 40-year-old 23-time grand slam champion said earlier this month that she would be "evolving away from tennis", strongly hinting that the US Open — where she is a six-time champion and 10-time finalist — would be her last.
For all the will in the world, Williams is unlikely to challenge deep in the second week given her indifferent form, leaving the women's draw typically wide open.
In the last 10 grand slams there have been seven different winners of the women's singles title.
In fact, since Williams won her last title, the 2017 Australian Open, there have been 15 different champions in 22 slams.
In comparison, that same period in the men's draw has seen just five different winners — and only two of them have been anyone other than the Federer-Nadal-Djokovic triumvirate.
So who is favourite?
Since her 37-match-winning run that culminated in her French Open title, 21-year-old Iga Świątek's form has been middling, winning just six of her 10 matches. So she is not an overwhelming favourite.
Simona Halep, Madison Keys, Paula Badosa and Cincinnati winner Caroline Garcia have all played well on hard courts this season so a winner could come from that cohort.
What happened in last year's US Open?
Raducanu pulled out one of the greatest performances at a grand slam of all time, becoming the first qualifier — man or woman — to reach a major final, let alone win the whole thing.
The final against Canadian star Laylah Fernandez was notable for the fact that it was the first time two teenagers had faced off in a grand slam final.
Raducanu won in straight sets, meaning she did not drop a single set in the entire tournament.
In the men's draw, Djokovic was within touching distance of becoming the first man since Rod Laver in 1969 to win all four of tennis's majors in a calendar year.
However, the pressure got to him, with Medvedev finally realising his potential to claim a career-first grand slam title in straight sets.
From an Australian perspective, Sam Stosur won the women's doubles with Zhang Shuai and Dylan Alcott completed his Golden Slam (all four major singles titles and the Paralympic gold medal) in the quad singles.
Who has won the previous grand slams this year?
The newly retired Ash Barty was victorious in her final professional match at the Australian Open, with her obvious successor as women's number one Świątek claiming the French Open on the clay of Roland Garros.
At Wimbledon, Russian-born Kazakh player Elena Rybakina claimed the women's title to claim her first grand slam trophy.
Rafael Nadal claimed his 21st and 22nd grand slam singles titles in the Australian and French Opens respectively, before Novak Djokovic claimed his 21st singles title on the grass of the All England club in London's south-west.
Djokovic beat Nick Kyrgios in that Wimbledon final, but that wasn't Kyrgios's only success this season at major championships.
Alongside Thanasi Kokkinakis, Kyrgios added more local success at Melbourne Park in a raucous men's doubles triumph, a feat emulated by Matthew Ebden and Max Purcell at Wimbledon.
When does the US Open start?
The first match of the 142nd US Open will get underway at 1:00am AEST on Tuesday August 30.
The finals will take place across the weekend of September 10 and 11 in New York, which means September 11 and 12 in Australia.
How do I watch the US Open?
The tournament has previously been shown on Foxtel, but this year Channel 9 has obtained rights for the US Open.
That means, for full coverage, you'll need to head over to the Stan Sport streaming service.