The Lions must win at Westpac Stadium, otherwise their Test series hopes will be over with one game - in Auckland, next Saturday - still remaining.
Guscott though, found himself in an identical position 12 years ago, when the 1993 Lions had to come good in Wellington or be faced by an irretrievable situation.
On that occasion, they got it exactly right, beating the All Blacks 20-7 thanks to a Rory Underwood try, Rob Andrew drop-goal and four Gavin Hastings penalties.
New Zealand ultimately took the series, but Guscott believes the 2005 Lions must believe they can draw level and ensure an Eden Park decider.
"The Lions are obviously still underdogs, but every player will be relishing the massive challenge ahead of them," said the former Bath and England centre, who played in eight Lions Tests from 1989 to 1997.
"Having beaten the All Blacks here in Wellington on the 1993 Lions tour, I know it is possible for international sides to turn things around in seven days, and I really hope that the Lions can do the same."
Woodward has reacted to the first Test demise by making sweeping changes, calling up seven new faces in Gavin Henson, Shane Williams, Steve Thompson, Donncha O'Callaghan, Simon Easterby, Lewis Moody and Ryan Jones.
He has also reshaped the back division, including handing new skipper Gareth Thomas outside centre duties instead of an injured Brian O'Driscoll and switching Josh Lewsey to comfortably his best position of full-back.
And Guscott praised Woodward's approach during a week when England's World Cup-winning coach took criticism from some quarters.
He added: "I am hugely impressed by this selection. It shows that Sir Clive Woodward is big enough to hold his hand up and admit that he made mistakes in selection last week.
"It looks to me like he has really taken on board what all the other (Lions) coaches think as well. It is a bold selection, and one that really excites me.
"When the All Blacks look at this side they won't know what to expect. That won't really make a difference to the way they approach the game, as they will always focus on just playing what is front of them, but it does make for a very exciting match.
"The Lions back-line looks much more threatening. Josh Lewsey runs such fantastic lines, that he is one of the most dangerous players in the world at full-back, and in my opinion, is better suited to the position than Jason Robinson.
"It is good to see Shane Williams being given a chance, and Gavin Henson too, while I think the selection of Gareth Thomas outside Henson is inspired. That combination should hopefully stop one of the All Blacks' most threatening players, Tana Umaga, muscling his way through midfield."
Guscott also believes a new Lions back-row of Simon Easterby, Lewis Moody and Ryan Jones can make an impression, with Easterby and Jones having shone despite only arriving on tour as respective replacements for Lawrence Dallaglio and Simon Taylor.
"That is the great thing about a Lions tour," said Guscott. "It is so unpredictable, and there are always surprises along the way, often with less well-known players stepping up to make a name for themselves.
"It is an opportunity which, up until now, has only been a dream for many of these players. Now that it is a reality, every single one of them will be buzzing.
"They will all be desperate to produce the performance of their lives, regardless of how much or little time they have had to train in these combinations.
"When it comes to make-or-break games of this nature, time is irrelevant. Being selected for the Lions in a Test match against the All Blacks is all the inspiration a player needs."