Daniil Medvedev battled cramp as he took just under three hours to beat Karen Khachanov in a gruelling first-round match at the Monte Carlo Masters.
Russia's Medvedev prevailed 7-5 4-6 6-4 against compatriot Khachanov in a match that saw 17 breaks of serve.
Ninth-seed Medvedev hobbled to the net at the end to shake hands with Khachanov and waved to the crowd, then immediately asked for the physiotherapist for treatment to his legs.
There were a combined 36 break points during the two hour and 51 minute match, with Medvedev saving eight of them and Khachanov 11.