Rio de Janeiro, Feb. 19 -- Thiago Agustin Tirante advanced to the quarterfinals of the Rio Open after top seed and compatriot Francisco Cerundolo retired due to a back injury during their second-round clash on Wednesday.
Tirante was leading 6-2, 3-1 when Cerundolo was forced to withdraw from the ATP 500 event, as per the ATP Tour website.
"It's not good to win like this, especially with Fran, one of my friends. Any moment, I didn't see anything," Tirante said.
"I knew that he was very tired from last week, so I had to improve myself on the court and focus on me," he added.
Cerundolo, who recently won the Argentina Open title in Buenos Aires, had entered the Rio tournament with momentum and secured a straight-sets victory over Mariano Na...