Tottenham manager Andre Villas-Boas has revealed that his ambition to progress in his career led to "the complete breakdown" in his relationship with former mentor Jose Mourinho.
Villas-Boas worked on Mourinho's staff during his spells in charge of Porto, Chelsea and Inter Milan, but the pair fell out in 2009 when the younger of the two Portuguese decided the time had come for him to forge his own path as a manager.
The former colleagues will go head-to-head for the first time on the touchline when Tottenham entertain Mourinho's Chelsea at White Hart Lane on Saturday, with the Spurs boss confirming the bond between the pair has long since been shattered.
"I don't lose any sleep," Villas-Boas said. "We had a great personal and professional relationship that we don't have now. I don't need to explain about our friendship. We still have mutual respect for each other. What we have been through together cannot disappear.
"Our break-up point was because I was full of ambition to give him something extra and I wanted further involvement for the job I was doing at that time, which was scouting and match preparation, but he did not feel the need to have another person near to him as an assistant.
"Therefore, I decided to think about my own career and started looking for a club in the summer of 2009. At that point, Jose wasn't sure if he would continue at Inter Milan anyway.
"When you work so close together for seven years, you learn methods and apply them as well. There is lots of things in my organisation that I do similar to him, of course."
Villas-Boas confirmed he will not be inviting Mourinho into his office at White Hart Lane for a glass of wine after the game on Saturday, as he will be making a quick exit after the game to attend an event celebrating Porto's 120 years of existence.
Even though Mourinho has played a huge part in the Portuguese club's history, he will not be making his way to his homeland for the event.