'What the heck': Dominic Thiem explodes over Red Bull gaffe

Second seed Dominic Thiem celebrated his 27th birthday with a commanding 6-3, 6-3, 6-2 victory over India's Sumit Nagal on Thursday, but it was a bizarre incident regarding a can of Red Bull that had fans perplexed.

Austrian Thiem, seeking his maiden grand slam title, won an overwhelming 74 per cent of his first serve points and fired seven aces past the inexperienced Nagal, breaking him seven times in the two-hour contest.

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But seeking some energy later in the match, in the heat, Thiem requested a can of a Red Bull energy drink.

Knowing Red Bull is not the sponsor of the tournament, the can logo must be shielded from television.

But Thiem was seething when the officials wanted the World No.3 to drink from a plain can, which the Red Bull had been poured into before entering court.

This did not sit well with Thiem, who wanted to make it clear to everyone that he was drinking Red Bull and adhering to anti-doping guidelines.

"Give me a plain cup, I'll somehow cover it and then I'll put it in... I mean what the heck is this?” Thiem was reported to have said.

After the match, Thiem clarified the incident, claiming it would have looked bad if officials had brought out a plain can and people were not aware what was inside.

‘They wanted to go out with the open can and fill it in a plain cup without me observing it,” Thiem said.

“That’s what pissed me off a little bit because the anti-doping rules are so strict. I don’t want to lose the can out of my sight...and they propose me to fill the can in a plain cup without me observing it.

“That pissed me off a little bit.”

But Thiem said it was settled and he went on to claim the match.

Thiem to face Cilic in Third Round

On Tuesday Nagal became the first Indian in seven years to win a singles match at Flushing Meadows but the 23-year-old showed only flashes of brilliance in a one-sided clash at Arthur Ashe Stadium.

Up next for Thiem, who was runner-up at the Australian Open this year, is 2014 champion Marin Cilic of Croatia who beat Slovakia's Norbert Gombos 6-3 1-6 7-6 (7-2) 7-5.

Spanish eighth seed Roberto Bautista Agut survived a difficult second-round match against Serbian youngster Miomir Kecmanovic with a 6-3 3-6 6-3 6-4 victory.

Bautista Agut, who could potentially play Australia's Alex de Minaur in the fourth round, squandered 14 break point opportunities but held his nerve in crucial moments to seal victory in just over two-and-a-half hours.