NEW YORK (AFP) — Novak Djokovic launches his quest for a 24th Grand Slam singles title on Monday as the US Open gets underway with the Serbian needing only a first-round victory to reclaim the world No. 1 ranking.

The 36-year-old Djokovic star makes a long-awaited return to the USTA Billie Jean King National Tennis Center after missing the 2022 tournament due to his refusal to get vaccinated.

Second seed Djokovic headlines the night session on the 23,000-seater Arthur Ashe Stadium with what should be a straightforward opener against France's world No. 84 Alexandre Muller.

A victory will guarantee Djokovic's return to the top of tennis's global rankings, regardless of how the rest of the US Open fortnight pans out.

Djokovic needs just 20 points to regain the No.1 ranking after defeating current No.1 and defending US Open champion Carlos Alcaraz in the Cincinnati Open earlier this month.

Alcaraz, who defeated Djokovic in a five-set Wimbledon final classic in July, opens his US Open campaign on Tuesday.

While most neutrals are hoping that Alcaraz and Djokovic can progress through to another blockbuster showdown in the men's final on 10 September, Djokovic said he is looking no further than Monday's opener.

"You can't really be thinking about what happens in three or four days," Djokovic said on the eve of the tournament.

"It's also in a way disrespectful to your next opponent if you're already thinking about your finals matchup, that kind of mindset never really resonated with me."

History suggests however that Djokovic's opener on Monday should be a formality: The Serbian has not lost in the first round of a Grand Slam since the 2006 Australian Open.

In other men's matches on Monday, American 10th seed Frances Tiafoe and ninth seed Taylor Fritz open their campaign dreaming of ending the host nation's two-decade long wait for a Grand Slam title.

No American man has won a Grand Slam singles crown since Andy Roddick lifted the 2003 US Open.