A ruthless 4-0 hammering in the Bernabeu last week left Tottenham facing a huge task to overcome Jose Mourinho's side and make the Champions League semi-finals.
No team in the history of the competition has been able to overturn a four-goal margin from a first-leg defeat, although three teams have managed it in other Uefa tournaments.
That said, those three teams were facing Borussia Monchengladbach, La Chaux-de-Fonds and Queens Park Rangers, and not team blessed with the world's best talent looking to conquer Europe for the 10th time.
But Redknapp cut a relaxed and optimistic figure yesterday, boosted by the news that Aaron Lennon could be fit for the match.
"We are in a situation where everyone feels the tie is over but we know we are a good team and can play well here at White Hart Lane," he said.
"We know it will take a miracle but miracles can happen and we have to believe that we can give it our best shot tomorrow and if we play very well, you never know what will happen.
"I went last year to see Juventus at Craven Cottage and Fulham were 3-1 down after the first leg and then went 1-0 down on the night early on. They came back and won the tie. It was one of the great games I've seen and shows that anything is possible.
"You never know with football. We have to turn in a good performance and see if we can win the game and we will see where it takes us from there. We will see how it develops."
Spurs came back from 3-0 down in the qualifying round against Swiss side Young Boys to make the group stages.
The attacking football that Redknapp has employed throughout the competition has endeared Spurs to many neutrals, but the manager admits he may have to rein in his team tonight, despite the four-goal deficit.
"It's OK saying you're going to attack them but you can't be that open," Redknapp said.
"You are playing against world-class players. You don't want to start bombing forward and be ripped open on the counter-attack and get hammered that way.
"You have to be controlled and take the chances when they come and give it our best go."
Spurs have enjoyed an excellent debut season in the competition, defeating both Milan sides, FC Twente, Werder Bremen and Young Boys to reach the quarter-finals.
Meanwhile, Uefa is sending a top disciplinary official to monitor the match tonight after Emmanuel Adebayor said English fans racially abused him in the first leg game last week.
Uefa has appointed Jacques Antenen, the vice-chairman of its disciplinary panel, as match delegate at the second leg in London.
10.45pm, Abu Dhabi Sports 3