Thomas Tuchel says that Paris Saint-Germain's defeat to Manchester United in the Champions League last 16 in March 2019 was the worst of his career.
Ole Gunnar Solskjaer was dealing with a 2-0 deficit from the first leg and a raft of injury problems but the Reds pulled off a memorable 3-1 victory in France to go through on away goals.
PSG dominated both legs and David de Gea was forced into a slew of brilliant saves to deny the French onslaught.
Tuchel grew demonstrably frustrated on the sidelines, while a controversial VAR handball handed United a last-gasp penalty which Marcus Rashford slammed home to secure passage into the quarter-finals.
It was another last-16 collapse from PSG, who had become infamous for their mental capitulations in the knockout stages of the competition, and Tuchel admits that the loss hurt him.
"I can be very honest after that match I was two days in a very dark place and I can tell you I was not able to speak to anybody and to think about anything else [other] than this defeat," Tuchel told reporters this week.
"That was maybe the worst defeat that I experienced because it came from nowhere. In the circumstances that it arrived, I was for two days in a dark place for a coach to be at."
Now at Chelsea, Tuchel will look to avenge the defeat on Sunday when his team play host to United.
Chelsea are yet to lose under Tuchel, who replaced Frank Lampard earlier this year, and they have the chance to move within three points of their visitors with a win. Tuchel says there is no way to compare the two games, but that he is eager to turn things around against the same opponent.
"There is no way you can compare these two games with each other," he continued. "I told you how I felt after this defeat in the Champions League. We all know that defeats are hard to digest. Am I a good loser? So so. Maybe not so much, but show me a good loser on this level.
"I would love to turn it around. We love the competition and we love to win and we love a good fight for it, and this is what we will hopefully get on Sunday."
United are coming off three excellent results, having eased their way into the Europa League last 16 and secured a 3-1 victory over Newcastle United last weekend. However, if they harbour hopes of challenging Man City for the Premier League title in the final weeks of the season, they must squeeze out another victory against Chelsea.
