Carlo Ancelotti told Jurgen Klopp that defeat at Napoli could yet again result in a Champions League final triumph for Liverpool after the Reds slipped to a 2-0 defeat at Stadio San Paolo.
Goals from Dries Mertens and Fernando Llorente condemned the European champions to their first competitive defeat since May 1 when Barcelona beat them 3-0 in the semi-final of last season's competition.
Napoli triumphed at home against Liverpool nearly 12 months ago before the Reds went on to lift their sixth European Cup in Madrid on June 1.
After the game, Ancelotti was seen smiling with Liverpool boss and the Italian has revealed how he backed his adversary for Champions League glory once more - despite again besting the German in Naples.
Two Reds outstanding despite defeat to Napoli - Liverpool player ratings
Ancelotti said: "I told him: ‘Don’t you worry, if you lose in Naples, then you end up winning the Champions League!
"I thank Klopp for saying we can win this competition, but it’s a long way to go. Now we must think about progressing to the knockout stages."
Ancelotti described Klopp's Reds as Europe's best team and detailed how he was able to nullify the threat of the Premier League leaders.
“The strategy was to play a complete game," he added. "High pressure if possible, but also defending deeper if needed.
"We did everything well. We have to get used to the different moments of the game. When Liverpool were in control we did well in defending and then took our chances.
"It was a very balanced game. So we did well, because I consider them the best team in Europe."
The Partenopei were given the lead in controversial circumstances when Jose Callejon went over cheaply under a challenge from Andy Robertson.
Referee Felix Brych pointed to the spot with VAR failing to overturn the call from the official .
“Just when it seemed that all was lost and Liverpool had taken complete control of the game, the two goals came from curious and unusual circumstances," said Ancelotti.
"[The penalty decision] was fairly clear from where I was in the dugout, but I don’t want to be drawn into an argument over that.”