Head coach Warren Gatland is hopeful that Brian O'Driscoll's latest injury is nothing to worry about ahead of this summer's Lions tour.
The Ireland centre suffered a back spasm during Leinster's RaboDirect PRO12 victory over Glasgow on Saturday.
The Lions squad assembled for the first time in London on Monday and the only absentee was O'Driscoll, who was told flying from Dublin would not be good for his back.
O'Driscoll has an Amlin Challenge Cup final and the RaboDirect PRO12 final to contest in the next two weeks.
And Gatland is keeping his fingers crossed that O'Driscoll's problem will not prove to be serious.
Gatland said: "Brian has been told to stay off his feet for 48 hours and this back problem is something that comes and goes.
"It normally takes just a few days to relieve the pain. We will keep our fingers crossed he is able to play in the two Leinster games that are coming up."
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