World number two Carlos Alcaraz has retired hurt after twisting his ankle in the first round of the Rio Open.

The two-time grand slam winner hurt his ankle after just two points while playing Brazilian Thiago Monteiro before the Spaniard went on to break his serve.

But just one game later, Alcaraz had his serve broken, shook Monteiro’s hand, and left the court shortly after, retiring from the match.

It comes a week after the 20-year-old lost to Chile’s Nicolas Jarry in the semi-finals of the Argentina Open.

After the match, world number 117 Monteiro said it was “strange” for an injury to occur so early in 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,” he said.

“Now I can only cheer for him to recover. He is a star, a dominant one in the new generation.”