Alexander Bublik has been criticized for an apparent slur that was picked up by on-court microphones during his first-round loss at the U.S. Open.

Former champion Dominic Thiem secured his first grand slam win in almost three years, defeating Bublik 6-3, 6-2, 6-4.

Thiem ended a seven-match losing streak at grand slams, which included a run of six consecutive first-round exits following his run to the Round of 16 at the 2021 Australian Open.

He was helped by an erratic Bublik, who committed 17 double faults and 44 unforced errors.

Thiem, who turns 30 on Sunday, saw his section of the draw open up further as fourth seed Holger Rune crashed out to journeyman Spaniard Roberto Carballes Baena.

Bublik has been slammed after he was accused of making a bizarre comment while expressing his frustration during the match.

“I’m f–king sick of getting all these disabled people back in their career,” the 25th seed from Kazakstan was heard saying, in a language other than English.

The slur appeared to be in reference to Thiem’s injury woes.

Bublik, who has a history of controversial on-court incidents, has also lost to veterans Gael Monfils and Stan Wawrinka this year as they returned from injury.

Tennis journalist Jose Morgado tweeted: “Bublik has losses against Monfils, Wawrinka (twice) and now Thiem in 2023. Tremendous lack of respect.”

Nick Kyrgios, who is missing the US Open with injury, said: “This is low key horrible.”

Thiem was asked about Bublik’s comment in his post-match press conference.

“I don’t know if the translation is right, you know,” Thiem said.

“If it is, then it’s a tough saying. Something you shouldn’t say in general just out of respect. But maybe he didn’t mean it that way or whatever. But what can I say about it.”

Thiem’s career has nosedived since his crowning moment in 2020, when he came from two sets behind to beat Alexander Zverev in that year’s pandemic-affected US Open final held without fans.

Once the world No. 3, Thiem’s ranking plummeted to 352 in June 2022 after a wrist injury sidelined him for nine months and prevented him from defending his US Open title.

“It was a very good match basically from the first moment on,” Thiem after the win over Bublik. “It’s a pretty special victory, because it’s the first since two-and-a-half years at Grand Slams,”

Next up for Thiem is US youngster Ben Shelton — one of 19 Americans who started in the men’s field.