Jacob Fearnley moved into an all-British meeting with Cameron Norrie in the French Open third round after his opponent Ugo Humbert retired following a nasty fall.
Fearnley, who replaced Norrie as the British number two earlier this year, was leading 6-3 4-4 when French 22nd seed Humbert quit.
Humbert tumbled as he stretched for a return at 40-40 in the eighth game and instantly clutched his right leg.
After receiving treatment, Humbert gamely tried to continue wearing heavy strapping and lost serve before deciding it would not be sensible to carry on.
As a result, 23-year-old Fearnley - who is 55th in the world after a rapid rise over the past 12 months - moved into the last 32 on his French Open debut.