The match went to penalties and Tottenham earned a first shoot-out win since 1994, and the north London club will now play a grudge match against West Ham, who won 3-0 at White Hart Lane three weeks ago, in the quarter-finals.
"We practised and practised penalties for the Basel game last year, but we didn't this time," Villas-Boas revealed.
"We haven't practised them for three or four months!
"We've seen some brilliant, brilliant football tonight. If you want to see predictable endings or happy endings you go to the opera or the theatre. In football you don't know what is going to happen.
"I couldn't be happier."
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