The winner-takes-all showdown follows wildly fluctuating Test matches in Brisbane and Melbourne when the rampant Lions triumphed 29-13, only to follow that startling success with a record 35-14 loss at Colonial Stadium.

And for captain Johnson, who led the Lions to a series triumph in South Africa four years ago, it would mean rugby immortality if his players come up trumps.

The Leicester and England skipper will be 35 when the Lions next tour - New Zealand 2005 - and accepts that tomorrow’s clash is realistically his last in the famous red jersey.

‘‘It would be fantastic for all the players to be involved in a Lions series victory a massive achievement,’’ he said. ‘‘Some of the guys have been part of it before, and all of us want to do it this time.

‘‘I can’t see me playing any rugby in 2005 at the highest level. There are a number of guys who appreciate that this is their last game ever in a Lions shirt.’’

‘‘And we are not going to come all this way, with all the hard work we’ve done, and roll over,’’ Johnson added.

‘‘It’s no time to roll over, it is time to roll up our sleeves and get on with it.’’

If the Lions prevail- and they have never lost a Test series against Australia then it will represent a major triumph over adversity, given losses through injury of players like Lawrence Dallaglio, Dan Luger, Mike Catt, Richard Hill and Rob Howley.

It is a fact not lost on Johnson.

‘‘There have been a few injuries, but look at the guys who’ve played. Probably no-one would have given Rob Henderson a chance of starting in the Tests, but he has done fantastically well,’’ he said.

‘‘When we lost Dan Luger everyone was very down about it, and rightly so, but Jason Robinson and Dafydd James have played very well on the wings for us.

‘‘Then we lose Rob Howley, and we’ve got Matt Dawson coming in, so there is strength in depth in the squad, as there should be.’’

The significance of tomorrow’s Test is not lost on Lions coach Graham Henry, whose ability to mastermind one-off victories is probably without equal in world rugby.

‘‘I don’t think they get any bigger, perhaps a World Cup final, but I haven’t been involved in any of those,’’ he said.

‘‘I think it is something that you are going to look back on over the years July 14 2001 at the Olympic Stadium in Sydney. It’s going to be a very important occasion for all those involved.

‘‘It is quite monumental, really - and historic - no matter which way it goes.’’

Henry’s plans suffered a hiccup today when centre Will Greenwood withdrew from replacement duty - Welshman Mark Taylor takes over - after experiencing a reaction to an ankle problem and suffering from flu.

Wing Austin Healey missed training today because of a slight back spasm, yet the coaching staff are confident he will be fit.

‘‘There is a lot of wear and tear, and the guys have played 11 months of rugby, which quite frankly is ludicrous,’’ Henry added.

‘‘You’ve just got to put up with those sort of situations over the weeks of this tour. That’s the nature of it you have just got to put up with it. It is frustrating but you cannot let the frustration get to you.’’

One player definitely starting is fly-half Jonny Wilkinson - unlike Stephen Larkham, his opposite number in Brisbane and Melbourne, who has a serious shoulder injury - and Henry saluted the England man’s restoration to full health.

Wilkinson was stretchered off at Colonial Stadium six days ago, nursing a potentially serious leg problem, but the recovery process has proved remarkably swift.

‘‘I think that James Robson (Lions doctor) and the medical staff have done a superb job, the way they looked at all the contingencies,’’ Henry said.

‘‘It could have been a serious injury, but they made sure that it didn’t develop into one.

‘‘We should give Jonny a huge pat on the back. He showed huge courage and fortitude this week to do what he’s done.

‘‘The respect I have for the young man is total. It just shows you his attitude, playing at the top level in international rugby.’’

While the Wallabies have lost Larkham, two other factors have not been lost on Henry Rod Macqueen’s last match as Australian coach and a Test debut for outstanding ACT Brumbies second-row prospect Justin Harrison.

‘‘I am sure that the Australians will want to send him (Macqueen) off with a positive,’’ Henry said.

‘‘He has done a marvellous job for the Australian team and there is no better way of thanking him than by doing the job on the paddock. That will be an extra motivation, for certain.

‘‘We think that Harrison is the best middle-rower we’ve played against on tour. We talked about the Brumbies game and said he was good enough to be in the Australian team I hope the Australian selectors weren’t listening to us.’’

The Lions will need to brush up on their set-piece work, given a malfunctioning Melbourne lineout, and a scrum that crumpled in an embarrassing heap ahead of Wallabies wing Joe Roff scoring his significant second try.

‘‘There are certain technical issues that we’ve looked at,’’ conceded Henry’s trusted coaching lieutenant Andy Robinson.

‘‘But a lot of it is about concentration and the tempo that we play at, particularly at the lineout, so we have looked at our lineout. We knew coming over here that every lineout was going to be keenly contested on both sides.

‘‘We’ve adapted our lineout slightly, and also our scrummaging. We scrummed well in the first Test, but we let them off the hook in the second.

‘‘They did us on a couple of scrums, and that was down to our mental concentration. We knew that Michael Foley (Wallabies hooker) was a very good scrummager, and I think that he has pulled the pack together.

‘‘He is very much ‘in your face’ and very proud of the way he scrummages. Obviously, we have been bitten now and we’ve just got to do something about it. The way to do that is to win the next game.’’

Whether the hordes of travelling Lions fans - probably now approaching 20,000 get their ultimate reward tomorrow remains to be seen.

After each side claimed comprehensive victories, the decider promises to be a tight, tense, nerve-jangling affair, undecided until the closing minutes.

One successful kick or one moment of magic could clinch it, and the Lions look better equipped in terms of individual match-winners.

‘‘We’ve had fantastic support out here and it was certainly a lift to the side away from home to have equal, maybe greater, support in the first Test,’’ Johnson said.

‘‘The occasion in Brisbane was massive and I am sure that it will be bigger still in Sydney tomorrow.’’

Party or wake? Sydney is ready either way, and as Wallaby great Mark Ella put it today: ‘‘This is shaping up as the biggest rugby union game in Australia for 12 years.

‘‘I wouldn’t be anywhere else but in Sydney this weekend.’’