Norfolk's Tom Youngs admits the British and Irish Lions' defeat to Australia in last weekend's second Test left him 'rock bottom' – but he still believes his team-mates can do the business in Saturday's highly anticipated Sydney decider.

A back spasm ended Youngs' involvement early in the second half of the 16-15 loss in Melbourne, but that was nothing to the pain of seeing the Lions' lead finally cancelled out late on as the Wallabies kept their hopes alive of a series win.

'The contrast in emotions is something I have never experienced before,' said the 25-year-old. 'The previous Saturday I was on top of the world and last weekend you feel as if you've hit rock bottom.

'But that's sport, that's why we play it, watch it and love it. We need to get the defeat out of the system and look ahead to the challenge of the weekend.

'We were all gutted to lose the game, and especially in the manner in which we did. But we've seen two great Tests and it all comes down to the wire in Sydney. It's all set up nicely.

'I had a bit of back spasm and that's why I came off. The doc gave me plenty of drugs so that has helped – it also helped to numb the pain of defeat too.'

The Leicester Tigers hooker will start from the bench at the weekend, while brother Ben has played his final minutes of the series after missing out on a squad place.

But Tom could yet make an impact form the bench play his part off the bench, with Welshman Richard Hibbard starting the action.

Some Queensland sun has been the order of the last few days for Warren Gatland's squad, as the Lions aim to end a 16-year losing streak for the Lions going back to 1997.

'We've had a few days rest and that's great. We were on the beach and in the sea – it's good to get a few days away from it because it's been a long tour, but all the boys are staying focused,' he added.

'You do need some downtime, but we'll be fully focused and ready for Saturday – you can be sure of that.

'You need to ease the pressure before you build it back up again. The lads will all do something together and that is what we were hoping for. We'll review the game and go into the third Test in good shape.'

Elsewhere, Brian O'Driscoll was hailed as 'one of the greats' by the player who will wear his trademark number 13 jersey on Saturday.

Ireland centre O'Driscoll had been expected to start his ninth British and Irish Lions Test and take over as captain from an injured Sam Warburton – until head coach Gatland dropped a selection bombshell.

Fit-again Jamie Roberts was called into the midfield, with Roberts' regular Wales midfield partner Jonathan Davies moving to outside centre. O'Driscoll did not even make the bench. But Davies has acclaimed the 34-year-old, whose fourth and undoubtedly final Lions tour will end with him watching rather than tormenting Australia's defence.

'What he (O'Driscoll) has achieved in the game, no other might do,' Davies said. 'He has been a great player. He might not like me saying it, but I've grown up watching him play.

'I have admired his work, and to have been able to play with him was very special. I have admiration for the man and a lot of respect.

'Brian is one of the greats because of what he's achieved in the game.

'I was very grateful to him for coming up and congratulating me. Everyone who isn't involved on Saturday has shown a professional attitude. That's been one of the positives of the tour.'

Davies arguably travelled to Australia a month ago with only an outside chance of a Test place, but he will end the tour by securing membership of an exclusive club.

Only six players – Davies, Leigh Halfpenny, George North, Jonathan Sexton, Adam Jones and Alun-Wyn Jones – will have started all three Tests.