The Cardiff Blues centre has been one of the revelations in the British & Irish Lions squad in South Africa, but damaged his right wrist in the second Test defeat in Pretoria last weekend.
Initial fears he may have fractured the joint were allayed by X-Rays and he returned to non-contact training on Wednesday. With co-centre Brian O'Driscoll already on his way home, the Lions can ill-afford to lose another key midfield player ahead of the weekend.
"Jamie is making good progress and he trained on Wednesday morning, although he didn't do any contact work. I am expecting Jamie to be fit to play," said Lions assistant coach Graham Rowntree.
"We will know more about him when he has done a physical session. Tommy Bowe trained, but Phil Vickery has a slight chest complaint, although we don't expect that to stop Phil from being available for selection."
Vickery could well find himself brought back into the Lions pack after being dropped for the second Test following his tough time against the Springbok front row in Durban. With Adam Jones on his way home with a dislocated shoulder, it will be between Vickery and late replacement John Hayes for the tight head spot.
Yet despite the difficulties the veteran England prop experienced against Tendai 'Beast' Mtawarira in the first Test, scrum coach Rowntree is backing him to bounce back if named in Thursday's team selection.
"It will be a huge psychological challenge for Phil if he starts the game, but it is one he is able to overcome. He is a strong character - one of the strongest I have ever seen in the game as either a player or coach," said Rowntree.
"If selected, it is going to be tough for him because by his own admission, and by my reckoning, he had an uncomfortable day at the office in Durban. But I will back him to get back out there and give a good performance."