England hopeful Dan Ward-Smith has been ruled out of the RBS 6 Nations Championship with a serious knee injury that could keep him out of action for up to six months.
The Bristol number eight dislocated his right kneecap and suffered a suspected ruptured tendon in a pile-up on his own line 15 minutes into his side's 14-8 Premiership victory over Northampton at Franklin's Gardens.
Ward-Smith wore an oxygen mask while medics were immobilising the knee before being stretchered off and taken to Northampton General hospital by ambulance.
A scan on Monday will determine the extent of the tendon damage but Bristol coach Richard Hill confirmed his chances of making his England debut will now have to be put on hold until this summer's tour to South Africa at the earliest.
Hill said: "The dislocated kneecap is probably a six-week injury with no complications.
"Although it was put back into place on the pitch, that's his Six Nations over," said Hill.
"But if he's ruptured his patella tendon then that's a six-monther and we just have to wait to see the results of the scan on Monday morning.
"It's a terrible thing to happen to a young man.
"It's really cruel luck for him and we all knew what it meant as soon as it happened - it really rocked our players.
"We didn't think about resting him from this game. Had we known he'd definitely been selected then maybe we would have done so, but he'd probably have wanted to play anyway."
The injury is a major blow to new England coach Brian Ashton's plans, with Ward-Smith expected to start the Six Nations opener against Scotland in place of former captain Martin Corry.
Instead the Leicester number eight - in towering form in the Tigers' historic European Cup win at Munster - may get a second chance, probably alongside Wasps flanker Joe Worsley and Sale open-side Magnus Lund.
The RBS 6 Nations Championship 2015 was not poised to go down as one of the more "vintage" Championships, though there was great anticipation as the action headed into its final day. What transpired was something that nobody could foresee: "The Greatest Day in Rugby's Greatest Championship."