Lions flanker Lewis Moody faces a race against time to be fit for first Test contention against New Zealand next week.
The Leicester forward has withdrawn from his place on the bench for Wednesday's clash against Wellington, when he will be replaced by his England colleague Richard Hill.
The Lions confirmed Moody had suffered an injury to his left knee in training, but the apparent seriousness was not revealed until coach Gareth Jenkins spoke to the media in Wellington on Tuesday.
Jenkins revealed that Moody is "out of the selection process" for next Saturday's game against Otago in Dunedin, and that will seriously hamper his Test prospects, given the Lions boss Sir Clive Woodward is likely to have finalised his first choice line-up by early next week.
Moody has not travelled to Wellington, remaining behind at the squad's Christchurch base for further tests.
Three players - Lawrence Dallaglio, Malcolm O'Kelly and Simon Taylor - have already been ruled out of the tour because of injuries.
The possible loss of Moody would be a huge blow, given his versatility at blindside and openside flanker, but it would appear the signs are not good.
Prop Andrew Sheridan, meanwhile, is battling to overcome an ankle injury sustained against the New Zealand Maori last Saturday, raising doubts about his prospects of being fit to face Otago. Like Moody, Sheridan is a serious candidate for the Lions' Test 22.
The British and Irish Lions team to play Wellington on Wednesday is:
J Lewsey (Wasps and England); J Robinson (Sale and England), B O'Driscoll (Leinster and Ireland, capt), G Henson (Ospreys and Wales), G Thomas (Toulouse and Wales); J Wilkinson (Newcastle and England), D Peel (Lanelli and Wales); G Jenkins (Cardiff and Wales), S Byrne (Leinster and Ireland), J White (Leicester and England), D Grewcock (Bath and England), B Kay (Leicester and England), S Easterby (Llanelli and Ireland), N Back (Leicester and England), M Corry (Leicester and England).
Replacements: G Bulloch (Leeds and Scotland), M Stevens (Bath and England), P O'Connell (Munster and Ireland), R Hill (Saracens and England), C Cusiter (Borders and Scotland), S Jones (Clermont Auvergne and Wales), S Horgan (Leinster and Ireland)
Matt Kvesic, skipper for the night at Newcastle, praised the young and reshuffled Gloucester side for their commitment at Kingston Park but regretted the fact that Gloucester couldn't capitalise on an ideal opening to the game.
Speaking with the local media before the Gloucester team set off on the long trip north to Newcastle, Director of Rugby David Humphreys discussed his team selection and stated that Friday night's meeting will be a challenging one.
Speaking to the local media on Thursday, Matt Kvesic was looking forward to the trip to Newcastle Falcons, and the captain is looking to lead from the front with plenty for the Cherry and Whites to work on.
Gloucester saw a 12-0 lead overturned by Harlequins on Friday night as the visitors ran out 22-15 winners. After the game, Director of Rugby David Humphreys spoke about missed opportunities on the night.
Elton John and his band will visit the home of Gloucester Rugby, Kingsholm Stadium on Sunday 7 June as part of their European tour. This will be Elton's first ever performance in Gloucester and tickets are on general sale from 9am on Friday.
Mitcheldean finance specialist Simplicity is proud to become the latest sponsor of Gloucester Rugby. Keen-eyed supporters will notice Simplicity's PayrollSimply logo on Gloucester's ball boy bibs, stadium billboards and programme adverts.