"We were good friends until we started beating them," Benítez said with a smirk as he sat in the Anfield trophy room, adding that his Portuguese counterpart "has a good relationship with the managers of the clubs that normally he beats". That being the case, Benítez will hope that the feud between two of the best coaches in European football has sunk to new depths by the time Chelsea depart Anfield after the second leg on May 1.
It is a source of hilarity to the Liverpool manager that Mourinho could still be heard, after victory in Valencia on Tuesday, talking about the "ghost goal" that he is convinced did not cross the line, scored by Luis GarcÍa in front of the Kop in the semi-final, second leg in 2005.
"I know Chelsea and they know us," BenÍtez said. "Always you must have confidence as a manager. We will see, but you know that Chelsea are a very good team and that in the last five years they have spent a lot of money on players and have a big squad.
"They may not accept what happened here two years ago, but they cannot change things now. They are a very difficult team to play against. What we will do now is concentrate on the Premier League and then concentrate on Chelsea."
Liverpool cannot match the ruthless efficiency of Chelsea or the individual brilliance of Manchester United and, as they breezed towards a straightforward second-leg victory over PSV Eindhoven last night, it was difficult to avoid the feeling that they may be the weakest of the semi-finalists.
However, that was also the case two seasons ago, when they overcame Chelsea and then defeated AC Milan in extraordinary circumstances in the final. That scenario could unfold once more this season, but Benítez will not need the bookmakers to tell him that his team must defy the odds again if they are to emerge triumphant in Athens on May 23.
The only real beneficiary of the evening was Peter Crouch, whose fifth goal in his past four appearances, midway through the second half, seemed more relevant on a personal note than in the context of the tie. Crouch scored against Chelsea in the Premiership at Anfield in January and, with seven European goals to his name this season, he is entitled to feel that he should have an important part to play against Mourinho's team again, particularly given the departure of Craig Bellamy on a stretcher after jarring his right knee in the early stages.
Nobody could accuse Liverpool of taking the easy route to the semi-finals after they overcame Barcelona in the last 16, but it seemed that fate was smiling on them from the moment they were drawn against PSV. Arsenal may beg to differ, having been beaten 2-1 on aggregate by the Dutch team, but, on the evidence of 180 minutes against Liverpool, that result seems more and more like an aberration on the part of Arsãne Wenger's team.
Liverpool deserve great credit for that after a 3-0 victory in Eindhoven that BenÍtez described as "perfect" in terms of his team's approach. It gave him the opportunity last night to rest Steve Finnan, Jamie Carragher, Steven Gerrard and Javier Mascherano. Incidents, let alone chances, were scarce. Had Jefferson Farfán scored with a third-minute header from Philip Cocu's cross, it might have been different, but José Manuel Reina reacted well and, with that, PSV's hopes disappeared.
They remained in the game, if not the tie, until the final half-hour, when they were reduced to ten men. Dirk Marcellis, an 18-year-old full back making his debut in the competition, caught Boudewijn Zenden with a late tackle, but there was astonishment among both sets of players when the teenager was shown a red card.
Within three minutes his absence had been exploited as John Arne Riise's left-wing cross was knocked towards his own goal by Carlos Salcido, forcing Heurelho Gomes into an awkward save. Robbie Fowler reacted well, clipping the ball back into the six-yard area, where Crouch pounced.
There was a festive atmosphere on the Kop, but the great European nights at Anfield have a common denominator: tension. There was none last night, but there will be when Chelsea visit Merseyside next month. The fervour of the Anfield crowd, allied to BenÍtez's tactical nous, will again represent Liverpool's best hope.