The frailties of Harry Redknapp's relegation-threatened side - who have not won in six Barclays Premier League games - were brutally exposed at a freezing, rain-lashed Turf Moor.

Burnley were two minutes away from Wembley after wiping out a 4-1 first-leg deficit before goals from substitute Roman Pavlyuchenko and Defoe gave Spurs an aggregate 6-4 semi-final victory.

That set up a final date with Manchester United at Wembley on March 1 but a furious Redknapp admitted afterwards: "We need stronger players in here because we're not mentally or physically strong enough."

Defoe went further in his assessment, claiming Tottenham would have struggled to cope with the humiliation had Burnley held on for the famous victory they arguably deserved.

The England striker said: "It would have been a nightmare if we had lost and would have been difficult to recover to be honest.

"Everyone knows it's not good enough, the manager knows and all the players know.

"Football is about confidence and at the minute the lads aren't that confident.

"But we're going through to the final and I suppose we can just look forward to that.

"The main thing was to go through but we wanted a better performance than that.

"We've got a lot of important games coming up now we so we just want to forget about this and look forward to the final.

"But we need to improve on our performances."

A growing injury list has left Spurs desperately short of players ahead of Saturday's trip to Old Trafford to face United in the FA Cup fourth round.

Jamie O'Hara picked up a groin injury at Burnley which will sideline him for several weeks and Jonathan Woodgate and Michael Dawson could also miss out.

Tottenham's home clash with Stoke in the Premier League next Tuesday has taken on huge significance as both sides are level on points with bottom club West Brom.

Redknapp is searching everywhere for new players, with a goalkeeper among his priorities, and Defoe admits current players could be shown the door.

"If the manager says that and if he wants to bring in his own players then I'm sure he'll do that," said Defoe.

"Everyone knows at the minute it's difficult for us.

"But it's not just us, it's the same for a lot of teams because this year the Premier League is so tight."

Defoe will come up against former strike partner Dimitar Berbatov this weekend as Spurs seek to defy the odds and reach the fifth round.

Berbatov has begun to show signs of his best form in recent games and Defoe never doubted the Bulgarian's ability to make the grade at Old Trafford.

He added: "I haven't seen Berba for a while so I'll look forward to that.

"He was always going to make an impact there because he's a great player.

"He's an international player, scored goals at every level, and he's doing well."

Defoe can understand why Redknapp ranks the FA Cup far below the Premier League on his list of priorities this season.

He added: "I understand why the manager is saying that because, with the position we are in in the league, that's got to be the priority.

"But if we can get through and win on Saturday we'll take that."