Tennis Fans Left Stunned at What Jannik Sinner Was Doing During US Open Final Delay

Tennis fans have been left in hysterics at what Jannik Sinner was doing during the delay to the US Open men's singles final.

The final between Sinner and Carlos Alcaraz was due to get underway at 2pm EST but faced repeated delays due to security provisions surrounding President Donald Trump.

Thousands of spectators were effectively locked out of the Arthur Ashe Stadium as security systems ground to a halt.

The delay meant a change to warm-up procedures for both Sinner and Alcaraz, who would have planned to be out on the court at a far earlier time.

Both players instead used a small backstage area to warm up.

Cameras panned to Sinner warming up using a small football, taking part in catching and juggling drills.

But the reigning US Open champion then stopped what he was doing, before hilariously deciding to chase one of his coaches around the room.

There was some method to Sinner's slightly unusual routine, as he was later seen doing short sprinting drills up and down the backstage area.

Players then entered the centre of the Arthur Ashe Stadium ahead of the revised 2:37pm ET start time - with thousands of spectators still locked outside.

Trump had taken his seat between the original start time and the delay, with Variety reporting that he received boos when shown on the big screen.

The final then got underway with many spectators still awaiting entry - which did not go down well with those outside the arena.

As for the tennis itself, Sinner and Alcaraz are competing in a Grand Slam final for the third time out of four events this season.

Italian star Sinner beat Alcaraz at Wimbledon, with the Spaniard winning their previous meeting at the French Open.

Sinner won the season-opening Australian Open by defeating Germany's Alexander Zverev in the final.