The British and Irish Lions remain hopeful that England prop Andrew Sheridan will be in contention for Saturday's second Test against South Africa
Sheridan is being treated for a back strain and he has not been involved for the Lions since last week's hard-fought victory over the Southern Kings in Port Elizabeth.
With Scotland international Euan Murray out of the tour due to an ankle injury, Lions boss Ian McGeechan has summoned front-row reinforcements in England's Tim Payne and Ireland tighthead John Hayes.
Both players start against the Emerging Springboks tomorrow, with Phil Vickery - who was destroyed by South Africa loosehead Tendai 'The Beast' Mtawarira in Durban two days ago and substituted after just 45 minutes - on replacement duty.
It leaves the door open for man-mountain Sheridan to make the Test 22, probably as bench cover for likely starters Gethin Jenkins and Adam Jones in an all-Wales front-row alongside hooker Matthew Rees.
"The medics are working on Andrew Sheridan, hopefully to have him fit for a full training session on Thursday," said McGeechan.
England Under-18 head coach John Fletcher insists his young side will be better for the experience after beating Italy in the bronze final to round out their 2015 Rugby Europe U18 Championship campaign in style.