The Sale forward was expected to be one of Scotland's leading contenders for a slot in the British and Irish Lions squad to tour Australia this summer.
But those hopes could now be dashed following the injury he sustained during the 28-18 loss at Murrayfield.
Gray will undergo a scan on Monday to determine just how long he will be out of action.
Scotland team doctor James Robson said: "Richie is due to be scanned at Spire Murrayfield hospital tomorrow with a view to a more accurate assessment of the injury he sustained on Saturday. At this stage I can confirm he will play no further part in this year's championship.
"It would be premature to speculate further at the moment. With the expert assistance of Spire tomorrow we'll have a better understanding then of the degree of injury to the muscle.
"Richie is on crutches at present and is grateful for the good wishes from supporters."
Dr Robson also confirmed that there were significant soft tissue injuries to a number of other Scotland players which will require further medical assessment but all are expected to be passed fit for the final game of the tournament in Paris on Saturday.
- Sports & Recreation
- James Robson