Mike Frey-USA TODAY Sports

World No. 2 Carlos Alcaraz of Spain rolled his right ankle and retired two games into his opening match at the Rio Open on Tuesday in Brazil.

Alcaraz, the top seed in the singles draw, was facing Brazilian wild card Thiago Monteiro in the first round. During the first game, Alcaraz returned a serve and began running laterally back to the middle of the court. Monteiro aimed his next shot behind Alcaraz, and when the Spaniard tried to stop on a dime, his ankle rolled and he fell to the ground.

Monteiro helped Alcaraz return to the bench, where he got his ankle taped. Alcaraz attempted to continue the match, winning the first game but being broken in the second.

"This is so strange," Monteiro said in a post-match press conference. "It was the second point of the match. On the court it didn't look so serious, but then I saw it in the big screen and it was a bad twist. Now I can only cheer for him to recover. He is a star, a dominant one in the new generation."

Alcaraz, 20, won the Rio Open in 2022 and finished runner-up last year when he lost the final to Great Britain's Cameron Norrie.

The 2022 U.S. Open winner and 2023 Wimbledon champion is one of the biggest stars in men's tennis, and it remains to be seen if his ankle injury will be severe enough to sideline him for any length of time.

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