Jack Draper has been ruled out of the French Open with a knee injury. It is another blow in the former world number four’s attempts to reestablish himself following the long-term arm injury that ruled him out for the best part of eight months. Draper has managed just nine matches across five events since returning in February and retired during his first-round clash with Tomas Etcheverry at the Barcelona Open earlier this month. He was subsequently diagnosed with an aggravated knee tendon injury and had initially hoped to return ahead of the second grand slam of the year next month. But Draper has now decided not to attempt to put his body through the rigours of best-of-five-set tennis on clay and will instead focus on recovering for the grass-court season. He wrote on his Instagram story: “My knee is on the mend and I’ve started back hitting balls but unfortunately I have been advised not to play Roland Garros.…