Dominic Thiem savoured his first Grand Slam match win since 2021 at his happiest hunting ground on Monday, as the injury-plagued former US Open champion downed Kazakh Alexander Bublik to reach the second round.

Thiem broke the Grand Slam stranglehold of Roger Federer, Rafael Nadal and Novak Djokovic by winning the 2020 title in New York but a wrist injury the following year sidelined him for months and other niggles meant his ranking slipped to 352nd.

The Austrian, now ranked number 81, has endured a dismal run at the majors since reaching the Australian Open fourth round two years ago and said beating Bublik 6-3 6-2 6-4 felt special.

"Yeah, it was a very good match basically from the first moment on. It's a pretty special victory, because it's the first since 2-1/2 years in Grand Slams," Thiem told reporters.

"I think, I don't know, six or seven Grand Slams without a match win. So it's great. Especially here at the US Open with all the past and all the memories I have here."

Thiem said he had slowly regained full strength in his wrist but rediscovering his confidence proved to be a challenge after his return in March 2022.

"The physical trust is there. Since the injury I've played many tournaments. I did many practice sessions. I really also gave a lot of load on the wrist again. It's completely fine," said Thiem, who meets American Ben Shelton next.

"The mental side wasn't easy to restore. Wasn't doing the same job I was used to before the injury, that wasn't easy.

"With every success, every match, especially with bigger successes or better weeks like I had in Austria when I played my first finals or also here ... it helps a lot on the mental side and to get full trust again in the wrist."

'LIGHTS OUT' DJOKOVIC CRUISES ON US OPEN RETURN

Novak Djokovic thrashed Frenchman Alexandre Muller 6-0, 6-2, 6-3 on his long-awaited return, guaranteeing he will take back the world No 1 ranking from Carlos Alcaraz.

The 36-year-old Serbian star, who missed last year's tournament over his refusal to be vaccinated against Covid-19, is chasing a 24th Grand Slam title and plays Spain's Bernabe Zapata Miralles in round two.

Djokovic, a three-time US Open champion, reeled off the opening eight games of the match before Muller belatedly got on the board, earning sympathetic applause from a crowd including former US President Barack Obama and his wife, Michelle.

The second seed showed little mercy to his overmatched rival, breaking serve eight times and clinching victory in an hour and 35 minutes.

"I started tremendously well out of the blocks," said Djokovic, whose match didn't begin until after 11pm following a ceremony honouring Billie Jean King and the 50th anniversary of equal prize money for men and women at the US Open.

"I knew it was going to be a late night for me, late start of the match. Nevertheless, I mean, I was excited to go out on the court," said Djokovic.

"I didn't care if I started after midnight because I was looking forward to this moment for few years, to be out on the biggest stadium in our sport, the loudest stadium in our sport, playing night session."

"Everyone knows in tennis that night sessions at Arthur Ashe definitely are the most exciting, fun, loud, energetic sessions you can have out there on the tennis world," he added.

Djokovic's previous match in New York was the 2021 final he lost to Daniil Medvedev, a defeat which stopped him from completing a calendar Grand Slam.

He improved his first round record at the US Open to 17-0 against Muller, who was making his main draw debut at the tournament.

"I think the performance explains how I felt tonight, particularly in the first two sets. It was kind of lights-out tennis really, almost flawless, perfect first set," said Djokovic.

"I've probably had the answer for every shot he had in his book. Overall I'm very, very pleased with the way I feel, with the way I'm playing.

"Hopefully I can maintain that level. It's just the beginning of the tournament, but I already like the level of tennis."