Roger Federer pulled out of what was possibly his last French Open on Sunday as a precautionary measure to rest up before Wimbledon, unwilling to risk his troublesome knee after an injury-plagued past 18 months. 

Federer, a 20-time Grand Slam title winner, who will be 40 in two months’ time, had battled over three-and-a-half hours until 12.45 am on Sunday morning to reach the last 16 in Paris.