Roger Federer and Rafael Nadal will be topping the bill in the US Open later today (August 31st) as the pair seek to continue their march towards what could be a titanic meeting in the semi-finals.
Federer came through a five-set scare against teenager Frances Tiafoe in the first round, having struggled with back problems in the lead-up to the tournament, but fans will remember that he also came into the Australian Open cold after months off and survived three five-setters to win the event.
The Wimbledon champion will take on Mikhail Youzhny, before world number one Nadal plays Japan's Taro Daniel.
If the pair do eventually progress to the last four, the question of who either might face in the final is a tantalising one, with the likes of Andy Murray, Novak Djokovic and Stan Wawrinka out of contention before a ball was served.
The situation has become even more fascinating after yesterday's action, with fourth seed Alexander Zverev tumbling out and 2008 Australian Open finalist Jo-Wilfried Tsonga following him. The most likely - and dangerous - opponent in the opposite half of the draw from Nadal and Federer is Marin Cilic, who will be keen to make up for his Wimbledon loss and repeat his 2014 triumph at Flushing Meadows. The other former US Open winner still in the draw - 2009 champion Juan Martin del Potro - is in the same half as the big two.
Fans booking corporate hospitality for the ATP World Tour Finals will have good reason to watch carefully who does make progress, as there could be some unusual names making it through to the O2 Arena this year. The likes of Djokovic, Wawrinka and Kei Nishikori will all be missing the rest of the year through injury.
While Cilic, John Isner or Kevin Anderson might be expected to reach the final, Kyle Edmund will see this as his big opportunity. He came through his second round match against American Steve Johnson in straight sets yesterday, but will face a tough test against rising Canadian star Denis Shapovalov, who defeated Tsonga 6-4, 6-4, 7-6.
If ever there was a time for Edmund to prove he can step up and mix it with the top players, this is surely it. Not only are many leading players on the treatment table, but with Andy Murray injured, Johanna Konta out in the first round and the other British singles players flying home, he carries British hopes in the singles.
There is good reason for British optimism in the doubles, however, as Jamie Murray and Brazilian partner Bruno Soares begin their title defence. The older Murray brother will be keen to ensure he is at the O2 in November, even if Andy has to go under the surgeon's knife.
In the Women's draw at Flushing Meadows, Venus Williams remains the favourite, but wildcard Maria Sharapova showed in her first-round victory over Simona Halep that a second US Open may not be beyond her. She defeated Timea Babos to advance into the third round yesterday.
With Serena Williams on maternity leave and Angelique Kerber going out in the first round, the women's draw is also opening up. However, with Wimbledon champion Garbine Muguruza and French Open winner Jelena Ostapenko still in contention, there are still plenty of big names in the running.
Image: Getty, from Keith Prowse subscription