The British & Irish Lions have been hit by a potential double injury blow ahead of Saturday's second Test against Australia in Melbourne.
Paul O'Connell and prop Alex Corbisiero are being "treated and assessed" for arm and calf muscle injuries respectively.
Ireland prop Tom Court, meanwhile, has been called into the squad and will go straight onto the replacements' bench for tomorrow's game against the Melbourne Rebels.
Ulster forward Court is currently in his home city of Brisbane following Ireland's North American tour, and he will meet up with the Lions squad later today
Corbisiero, who joined the Lions tour as front-row cover earlier this month from England's two-Test trip to Argentina, went off early in the second half as the Lions beat Australia 23-21 at Suncorp Stadium on Saturday.
Mako Vunipola – a probable second Test starter if Corbisiero is ruled out – has been withdrawn from the match-day 23 for the Rebels clash.
O'Connell's injury, meanwhile, must be of huge concern to the Lions.
The 33-year-old second-row talisman has featured in seven Lions Tests and was the 2009 tour captain in South Africa. He has won 85 caps.
He is an integral part of coach Warren Gatland's plans and, if he is ruled out of the Test series then it would represent a colossal blow.
Should O'Connell not make the second Test, then England and Leicester lock Geoff Parling would be favourite to replace him, partnering Alun-Wyn Jones in the second row.
The Lions initially looked to have emerged trouble-free from a bruising opening Test – unlike their opponents, who had three backs – Berrick Barnes, Pat McCabe and Christian Leali'ifano – carried off,.
But it now appears that Corbisiero and O'Connell are both struggling for Melbourne.
On the positive side, centres Manu Tuilagi and Jamie Roberts are in contention to make it after recovering from respective shoulder and hamstring injuries, along with wing Tommy Bowe, who had a broken hand
Gatland said: "To have Tommy and Manu fit and back is a great compliment to the medical staff.
"Tommy is fit for Saturday, he's running, but the more time he has to heal the better.
"The surgeon said that injury is normally a six to eight-week injury, so to be fit in three weeks is magnificent.We don't think Jamie is too far away and is potentially available for the weekend."
