Shane Geraghty is doubtful for England's RBS Six Nations clash with France next Saturday after suffering a knee injury.
The London Irish centre was withdrawn during the first half of the Exiles' Guinness Premiership win over Leicester on Sunday.
London Irish assistant coach Toby Booth said: "He has hyper-extended his knee.
"The swelling continued through the match and it got to the stage where it wasn't worth the risk."
He admitted: "There was an element of precaution," but when pressed on Geraghty's chances of being involved with England this week, added: "It's too early to say."
Geraghty picked up the problem in the opening exchanges after playing a leading role in the Exiles' first try, scored by Richard Thorpe. London Irish went on to win the match 22-13.
England coach Brian Ashton will now have to wait for further news after including Geraghty in a 31-man squad for the game in Paris.
But London Irish scrum-half Paul Hodgson has done enough to gatecrash his way into England's squad to face France, according to club boss Brian Smith.
"I think Paul Hodgson today played himself into the England 22," said Smith.
Hodgson, named in the England training squad with Harlequins veteran scrum-half Andy Gomarsall and Sale youngster Richard Wigglesworth, turned in a man-of-the-match performance.
Smith added: "There's three blokes currently in the running and, for me, Dodger's jumped ahead of one of them.
"There's been some question marks about the other scrum-halves' form and if Brian Ashton saw his performance today, it was courageous.
"When you go to France you're going to need people to front up and I think - dangerously for our club because we need him - that he's played himself into the England 22."
He insists he will have no worries if England coach Ashton plunges Hodgson into the international cauldron in Paris.
"Paul Hodgson's not being thrown into anything. He's played over 100 first class games and, arguably, half the Premiership games are more intense than half the Six Nations games.
"He's very well matured, a great rounded player and he's got more experience than one of the scrum-halves there and a lot more legs than the other bloke. I think he deserves his chance."