The 66-year-old had led Tottenham to a top-four finish and the north London side looked to have qualified for the Champions League for the second successive season.
However, Chelsea’s penalty shoot-out triumph against hosts Bayern Munich ensured the Blues took England’s final spot in Europe’s premier competition, relegating Spurs to the Europa League.
Redknapp, who was invited to the final by his son Jamie, was sacked a mere matter of weeks later and Daniel Levy appointed André Villas-Boas as the Englishman’s successor at White Hart Lane.
“I made one of the biggest mistakes of my life the night I went to watch Chelsea win the 2012 Champions League final,” Redknapp wrote in his autobiography, Always Managing, which is being serialised by Daily Mail.
“You all know what happened. Chelsea were outplayed by Bayern Munich — as they had been by Barcelona and by Napoli in previous rounds — but they won the trophy.
“It meant Spurs hadn’t qualified for the following season’s Champions League, despite finishing fourth — two points above Chelsea in the Premier League. They took our place as holders.
“I was distraught. I felt like crying.”
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