A blockbuster final awaits between two of the biggest names in tennis, with both Del Potro and Djokovic fully deserving of their place in the final. As is the case in most of his matches, fan-favourite Del Potro will have the majority of the crowd supporting him...
Two power players meet in the US Open final on Saturday but that is where the similarities end as six-time winner Williams is seeking a record-equalling 24th Grand Slam title whilst her 20-year-old Japanese opponent is appearing in her first major final.
Nishikori and Djokovic possess very similar games in that they are both great defenders from the back of the court, they move incredibly well and they like to dictate from the baseline, but the fact of the matter is that Djokovic is superior in all those departments and has a few extra weapons in his arsenal that Nishikori doesn't possess.
The fact that Nadal is still in with a chance of defending his US Open crown is testament to his incredible fighting qualities as there have been several occasions where it looked like he might be bowing out of the competition.
Millman will undoubtedly be carrying confidence from his shock fourth-round win but a key factor behind that success was the fact that a struggling Federer played nowhere near his best and made an unprecedented 76 unforced errors.
This will be the fourth meeting between these two at the US Open and their 15th overall, and it has been a rivalry often decided by narrow margins. Their contrasting styles make for a fascinating match-up, with Nishikori's excellent backhand and solid defence countering Cilic's big serve and aggressive forehand.
This will be the 11th meeting between these two players but all previous encounters have come on clay so it will be fascinating to see how their games match up on a different surface.
Two of the most powerful players on tour meet in the quarter-finals and history tells us this is likely to be an incredibly tight match with one or two tie-breaks to be expected. Isner's serve will be key to his chances as he will look for free points as often as possible due to Del Potro's edge when it comes to baseline rallies.
Millman has rightfully earned his place in the fourth round after some hard-fought victories over tough opponents but hard work alone will not be enough against an opponent such as Federer, who delivered a masterclass in shotmaking against Millman's fellow countryman Nick Kyrgios on Saturday.
Djokovic has survived one or two testing moments so far in his bid for a third US Open title but he produced an excellent performance against Gasquet on Saturday and has been handed an admittedly kind fourth-round draw so it is fully expected that he will reach the quarter-finals.
This will very much be a case of attack vs defence as Del Potro will look to dictate with his thunderous forehand and overpower the impressive Coric defence.
Nadal survived a bruising third-round encounter with Karen Khachanov on Friday in which the Spaniard was forced to produce some of his best tennis to emerge victorious. Here he faces an opponent in Basilashvili who is enjoying the best year of his career but this is likely to be as far as the Georgian goes at the US Open.
Although Djokovic has not been at his brilliant best at Flushing Meadows so far, he tends to grow into tournaments and this is a match-up that has long been favourable for him. The pair have met three times previously at Grand Slam level, and on each occasion Djokovic has won in straight sets.
These two have served up some tight battles previously as the unpredictable Kyrgios tends to raise his game when facing Federer and does already have a win against the Swiss on his record. Federer's form so far has been solid if not spectacular but this is by far his toughest test yet and it has all the makings of a classic contest.