His chances of making history were boosted when Federer announced he would be undergoing a third knee surgery since the start of 2020 and missing “many months” on tour, before Nadal later cut his season short to recover from an ongoing foot injury.
The world No 1 was also the only member of the Big Three to play in Flushing Meadows last year, in what was one of the first events since the tour was suspended during the pandemic, but failed to capitalise in their absence.
Djokovic’s opener against Rune marked his first match since he was defaulted during his round of 16 match against Pablo Carreno Busta in 2020.
The 20-time Grand Slam champion he hit a ball away in frustration which unintentionally made contact with a lineswoman after going a break down and giving the Spaniard a chance to serve for the first set at 6-5, and was immediately disqualified.
The 2021 US Open is now being played with automatic line calling on all courts, with no line judges.