Robson developed the clots spontaneously, rather than as a result of a contact injury

Dan Robson has developed blood clots and he is unlikely to play again this season, dealing a serious blow to his hopes of gaining selection for the World Cup in Japan in the autumn.

The Wasps scrum half was due to be on the bench against Scotland today but he left England’s training base on Tuesday after alerting the medical staff to a pain in his leg.

Robson, 27, who has two England caps, developed the clots spontaneously, rather than as a result of a contact injury. He was taken for immediate medical treatment because the condition can be life-threatening. Blood clots can form in veins or arteries.

Specialists are investigating the cause of the problem, with Robson due to undergo tests this weekend. It