Portugal Colonial - Former champion Thiem's Grand Slam career over

The injury-plagued former world number three went down to a 6-4, 6-2, 6-2 defeat to American 13th seed Ben Shelton, his eighth first round exit at his last 10 Slams.

Thiem had already announced his intention to retire from tennis on home ground in Vienna in October, giving up on his fruitless battle to fully recover from a persistent wrist injury.

When Thiem captured his first Slam by defeating Alexander Zverev from two sets down in the 2020 US Open final, it appeared that he was finally poised to challenge the likes of Roger Federer, Novak Djokovic and Rafael Nadal at the highest level.

It also ended a sequence of three defeats in three Slam finals -- to Nadal at the 2018 and 2019 French Open and against Djokovic in five sets at the 2020 Australian Open.

However, his career went into a tailspin in the summer of 2021 when he suffered a wrist injury at the Mallorca ATP tournament.

Thiem suffered serious ligament damage and was forced to sit out the rest of 2021.

He played just two Slams in 2022 and his ranking fell to outside the top 100 for the first time in over a decade.

"I just want to say thanks for all the support. It's been 10 years since I first played here, I had my greatest success on this court," said Thiem whose 2020 triumph was witnessed by just a handful of people with the tournament played out at the height of the Covid pandemic.

"But when I won in 2020, it was weird. It was under very strict conditions and I had my success without any of you here.

"So I am super-happy to get the chance to play in front of you and on this court. Thanks to you for making up the time that we missed."

Heading into the US Open, Thiem had won just two main draw matches all year, the most recent was at Estoril in the first week of April.

He needed a wildcard to play in New York with his ranking having slipped further to 210.

Shelton was full of praise for Thiem, the winner of 17 career titles and more than $30 million in prize money.

The pair exchanged warm words at the net before Shelton guided the crowd to applaud his rival.

"I want to say congrats to Dom for an outstanding career. Four Grand Sam finals and a title, it's the kind of things kids dream of sitting at home on the couch," said Shelton. "That was me not too long ago."

"It's always great seeing Dominic around, he's always smiling. So many people love him."

L.Mesquita--PC