British and Irish Lions captain Sam Warburton playing for his spot against Waratahs

LIONS captain Sam Warburton has 80 minutes against the Waratahs to prevent the bizarre scenario of missing selection for the first Test.

LIONS captain Sam Warburton has 80 minutes against the Waratahs tomorrow night to prevent the bizarre scenario of missing selection for the first Test, and forcing an all-new skipper to lead the Lions into battle against the Wallabies next week.

Warburton's challenge was made clear yesterday as coach Warren Gatland stood firm behind his stance that not even a Lions captain was assured of a Test spot, and also revealed a mounting injury crisis among his backs.

Led by Warburton, the Lions side to take on the Waratahs was named yesterday but due to injury concerns and "sore bodies", Gatland was unable to observe tradition and put out a Test team for a final dress rehearsal.

Though Jonny Sexton (hamstring) was cleared, Brian O'Driscoll (groin), Manu Tuilagi (shoulder) and George North (hamstring) are on the treatment table. Such is the concern, Gatland flew in English centre Billy Twelvetrees as midfield cover yesterday.

"Ideally, you would like to go pretty close to a shadow (Test) team but we haven't done that," Gatland said.

"We have a few knocks in the backs at the moment, and we had to rest a few players to make sure we arrive in Brisbane next Saturday fresh and ready to go."

One man aiming to use the Waratahs clash as a platform to win a Test spot is, surprisingly, the Lions captain.

The tourists' back row is the area of hottest competition for spots, with Warburton, Sean O'Brien and Dan Lydiate vying for the No.7 jersey, and with Tom Croft, Jamie Heaslip and Toby Faletau offering no vacancies elsewhere.

Gatland made it clear last year whoever he made tour captain would not automatically be Test captain as well.

"It's about picking the best players. I haven't changed that tune and Sam is well aware of that," Gatland said. "The performance on Saturday is important for Sam, as it's important for Jamie and Tom Croft. There's competition there. It's one position we haven't got any injuries, everyone is firing. From that point, it's going to be a long night in making the decision when we do pick the Test back row."

After a knee injury early on tour, Warburton has played just one game against the Reds but conceded the quality of opposition would count in his final selections.

Gatland welcomed the addition of Wallabies Dave Dennis and Rob Horne to the Waratahs side, and said he'd been impressed with NSW's work this season.

"Watching the Waratahs at the moment, technically, they're excellent," he said.