(Reuters) - The men's draw at a Grand Slam has seldom had such an overwhelming a favourite in recent times as Novak Djokovic at this year's U.S. Open, with lot more at stake for the world number one than just his 18th major title.

It took the COVID-19 pandemic to put a brake on Djokovic's 18-match unbeaten run in 2020, as he won the ATP Cup with Serbia, an eighth Australian Open title and a fifth Dubai Tennis Championships before the season came to a halt in early March.