British and Irish Lions 2013: We've still got a fantastic display in us, says Andy Farrell

Wallabies rose to one do-or-die challenge, now it's our turn, says Lions' Mr Motivator

Andy Farrell admitted the Lions must work on their set-pieces (Getty)

The Lions have been driven by a high emotional charge for a fortnight now and may even have short-circuited themselves ahead of the Melbourne Test by turning the switch a notch too far, but the great motivator on their coaching staff believes that despite the failure to clinch the series when they had the chance, they can still start this weekend's decider in Sydney in a better frame of mind than the Wallabies.

"I experienced it often when I was playing rugby league: you get yourself right up for a big semi-final and then struggle to replicate it a week later," said Andy Farrell, an acknowledged maestro of the 13-man code. "Last weekend in Melbourne, it was do or die for the Australians. Fair play to them, they rose to the challenge: I thought they deserved to win, definitely. But it was still a one-point ball game and it could have gone either way. The question is: can they get up again, having worked so hard to play themselves back in the series?

"With us, there's still a bit of emotional reaction to the enormity of the game at the weekend. That's understandable because there was so much at stake, but there's no doubt in my mind that we can turn this around. And at this stage, fatigue won't come into it. If you asked the players now if they wanted to go again tomorrow, they'd jump at it. That's what big-game players want to do when they lose such an important match: get back into it straight away. There is a fantastic performance in this side and we haven't seen it yet, even if we've seen some very good ones."

Farrell acknowledged that there would be a good deal of focus on the Lions' set-piece work – scrum and line-out – in the build-up to the Sydney date. "Clean ball is everything," he said, aware that quality possession was a rare luxury for the Lions in Melbourne. He did, however, add that he felt the scrum was "a bit of a lottery", congratulating the Wallabies in ironic tones on their expertise in "playing the referee".

At this stage, it seems inevitable that the coaches will make significant changes to their line-up, possibly in every area of the team bar the back three, where Leigh Halfpenny, Tommy Bowe and George North are virtually certain to continue. Jamie Roberts will come into consideration at centre if fit, as may Manu Tuilagi; Mike Phillips is expected to return at scrum-half; and there could be wholesale changes to the pack, with Alex Corbisiero, Richard Hibbard, Richie Gray, Ian Evans, Tom Croft, Sean O'Brien, Justin Tipuric and Toby Faletau all likely to have their widely differing claims discussed.

"We have to make sure the people we pick are fully fit, because we can't carry passengers in a game like this, and we must decide whether we need to freshen things up," Farrell said. "First of all, we'll talk to the strength and conditioning guys, together with the medics, and work out who's right for this game and who might be beginning to flag. Whoever we pick will be a big-game player."

Today, the Wallabies will discover whether James Horwill, their influential captain, can face the Lions in Sydney. The Queensland lock faces what is in effect a retrial after being acquitted of stamping on the head of Alun Wyn Jones in the Brisbane Test – a verdict appealed by the International Rugby Board. The Canadian lawyer Graeme Mew will conduct the case via video link.

Final countdown: five things Lions must do for Saturday's decider

1) Sort out the scrum

Against all expectations, the Wallabies bossed the set-pieces at the end of the Brisbane Test and bossed them again early on in Melbourne. The common denominator? The absence of Alex Corbisiero. If the medics can get the loose-head prop fit for the finale, they will do the tourists a huge service.

2) Secure the line-out

The official statistics point to a relatively effective Lions line-out in Melbourne, but no one with eyes to see would describe it as a convincing performance. The pack too often produced unusable ball, thereby erasing attacking options. The simple solution would be to find a place for Tom Croft in the back row.

3) Make Will Genia suffer for his art

Someone needs to get hold of this bloke, fast. The outstanding performer in the series, the Wallaby scrum-half is at the very heart of their operation. His footwork is ultra-clever and his instincts are razor-sharp, and if the Lions are to win in Sydney, they must find a way of subduing him.

4) Second-guess the referee

The Lions forwards will be more familiar with this weekend's official, Romain Poite of France, than with either of his predecessors. This knowledge must be made to count, and if it means indulging in the kind of kidology the Wallabies used in Melbourne, so be it. All's fair in love and war.

5) Show some ambition

Sixteen years ago, during the half-time interval in the famous Durban Test, the centre Jeremy Guscott pleaded with his team-mates to "play some *@?#&%! rugby". It is easier said than done, but the Lions will surely have to score at least one try to prevail in Sydney. Goal-kicking alone is unlikely to suffice.