Russian tennis player Karen Khachanov on Thursday reached the Halle Open quarter-finals after the withdrawal of Japan's Kei Nishikori due to injury.
After receiving medical treatment on the court to treat a back injury, the World No.9 Japanese player opted to pull out after 34 minutes, with the score at 3-2, reports Efe.
The 21-year-old Russian now advances to the quarter-finals to play against the winner of the match between his compatriots Mikhail Youzhny and Andrey Rublev.