Chelsea took the lead two minutes before half-time when Didier Drogba out-muscled William Gallas and fired a ferocious strike past Carlo Cudicini.
And Roberto Di Matteo’s men were awarded a controversial second in the 49th minute as referee Martin Atkinson judged Juan Mata’s effort to have crossed the line – replays showed the Spanish midfielder’s shot was blocked by captain John Terry.
Spurs responded with Gareth Bale finishing from close range – but Chelsea restored their advantage and stretched their lead when Ramires lifted his shot over Cudcini, before Frank Lampard and Florent Malouda netted in the final 10 minutes to set up a clash with Liverpool next month.
“I thought we were the better team in the first half and didn’t deserve to be behind at half-time,” said Redknapp.
“We hit the post, had one cleared off the line but then found ourselves 1-0 down after a wonder goal when we really should have been in front.
“I said at half-time that we’d played well and we had to keep believing, we were 1-0 down but didn’t deserve to be and that there was a game for us to win.
“The second goal is nowhere near a goal, but I wouldn’t want to make excuses. It was an honest mistake. I’m not going to sit here and say that’s why we lost the game, but it doesn’t help when you get a goal like that given against you.
“We got back into the game at 2-1 and I thought we were right in it then.
“I took a gamble then, brought on Jermain and went with four forwards. We needed a goal at that time but when you do that, you leave yourself open and they picked us off. We got punished in the end.
“It’s a big disappointment for everyone, us, the fans and we’re sorry how it’s gone but we’ve got to start again.
“We’ve still got a massive chance to finish fourth and we have to make sure we do it.”
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