Red Bull's Max Verstappen was fastest in final practice for the showcase Monaco Grand Prix on Saturday with Formula One championship leader Lewis Hamilton struggling in seventh for Mercedes.
Grid position is critical for Monaco, where overtaking is almost impossible, and Hamilton appeared to be in some difficulty.
The seven-times world champion, winner from pole last time Monaco hosted a race in 2019 and before the Covid-19 pandemic, was 0.726 off the pace.
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"Unfortunately, it looks to be game over for Mercedes. They just don't have the grip out there and can't get the tyres to work," commented Mercedes' 2016 world champion Nico Rosberg on Sky Sports television.
"They are really up against it. They are stuck, they are in a corner, and I don't have too much hope for them at the moment for qualifying."
Hamilton's team mate Valtteri Bottas was fourth, with Mexican Sergio Perez fifth for Red Bull and Lando Norris sixth for McLaren.
The hour-long session was brought to a close by Mick Schumacher crashing his Haas at the exit to Casino Square.
The chances of Schumacher's mechanics getting the badly damaged car ready in time for afternoon qualifying looked remote.
"I don't know what to say, I'm very sorry about that," said the German rookie over the team radio.
Canadian Nicholas Latifi had earlier crashed his Williams, bouncing off the kerb and into the barriers and halting the session with 17 minutes to go while the car was removed. (Reporting by Alan Baldwin, editing by Ed Osmond)
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