Adebayor had scored his first goal of the season to put Spurs 1-0 up after 10 minutes at the Emirates Stadium, but his sending off seven minutes later changed the course of the match which his former side Arsenal won 5-2.
Going in high for a loose ball in midfield, the striker caught Cazorla with his studs up and was shown a straight red card by referee Howard Webb.
Accepting he let his team mates down, Adebayor told The Sun: "I completely understand my sending off changed the entire outcome of the game and I whole-heartedly apologise to my team mates, the manager and all the Tottenham fans for letting them down.
"But I must stress that my challenge was not malicious in any way whatsoever.
"I was genuinely trying to win the ball and probably stretched my foot out a bit too far in the heat of the moment.
"Nobody could have felt more devastated than me as I walked off the pitch. I so much wanted to help Tottenham win and thought for a moment that I'd actually set that win up when I scored, but football changes so quickly. One minute a hero, the next a villain."
Spurs manager Andre Villas-Boas refused to blame the Togo international, saying: "The red card did not change the game. Ade did not go in to harm Cazorla. Cazorla is quick, he reacted and took the ball away before Ade's feet met his foot."
It was the second successive season Spurs have lost 5-2 at Arsenal after taking the lead in the north London derby which has now produced 121 goals in 41 meetings since the Premier League began in 1992-93 - more than any other fixture.