Bayern Munich manager Thomas Tuchel admits he is having sleepless nights before his side's Champions League meeting with Manchester City.
Tuchel returns to England for the first time since he was sacked by Chelsea in September when City host the quarter-final first leg on Tuesday (20:00 BST).
In 10 previous meetings, Tuchel has only beaten a side managed by Pep Guardiola on three occasions.
"I will try to go to bed early. I hope I will be able to sleep," he said.
"The best preparation is sleep but sometimes it is hard to get that sleep when you're thinking about things.
"This morning I woke up really early and I just decided to go to the training ground because I couldn't get back to sleep. I just kept thinking about the match."
Tuchel's last win over Guardiola came in 2021, when Chelsea beat City in the Champions League final for the first of three trophies the German won in his 20 months at Stamford Bridge.
City went on to twice beat Chelsea in the Premier League before Tuchel's departure, while they have not faced Bayern since November 2014 when, under Manuel Pellegrini, they beat the Bundesliga side 3-2 to reach the last 16.
Tuchel, who replaced the sacked Julian Nagelsmann at league leaders Bayern in March, says his side will need to be at the "top of our game" in order to beat City, who have won their past eight games in all competitions.
"I don't think I can learn much from other games I've played against Pep," he said.
"It's unique what Pep does. We'll try to find solutions but we'll need a complete performance to create problems for City."
He added: "It is a major task in front of us. I was just outside [at Etihad Stadium] and that is the current gold standard for us.
"We want to live up to that but the team is entitled to be confident after our results and performances in the Champions League so far and we have to try to continue like that.
"Maybe we play in a role of slight underdog, which is not a problem. We'll try to make the most of it. We need to be confident and on top of our game."
Tuesday's match will see Bayern full-back Joao Cancelo return to Manchester for the first time since his January loan move from City.
The 28-year-old Portugal defender fell out of favour at the club and moved to Germany for the remainder of the season, with Bayern having the option to sign him for 70m euros (£61.4m) in the summer.
Tuchel said he is "happy" Cancelo is in his side but discussions have not taken place as to whether Bayern will make his move permanent.
On Cancelo facing his parent club, Tuchel said: "I hope he can manage his emotions and he is not over-motivated and over-excited.
"But I also hope he is not too shy. It is not enough to know it. A lot of people know smoking is bad for you but they still do it."
