Ferrari’s Charles Leclerc has suffered the latest of a series of blows to his title hopes with a grid penalty for excessive engine usage.
Ferrari have fitted a third electronics control unit at the Canadian Grand Prix, triggering an automatic 10-place grid penalty for Sunday’s race.
Teams may use only two electronics units per driver per season.
Leclerc has suffered an 80-point swing in favour of title rival Max Verstappen after a series of recent problems.
And he is now likely to lose further ground to the Red Bull driver in Montreal.
Leclerc led Verstappen by 46 points after two victories and a second place from the first three races, from two of which the Dutchman retired.
But Leclerc has suffered two engine failures in the last three races, both times when he was in the lead.
He also lost victory in the Monaco Grand Prix after a Ferrari strategy bungle dropped him from the lead to fourth, while a spin in the closing stages of the Emilia Romagna Grand Prix turned a third place into sixth.
As a result, he starts the Canadian Grand Prix 34 points behind Verstappen, who ended Friday practice fastest after an impressive day in the Red Bull.
The world champion was 0.081 seconds clear of the man who until not too long ago appeared to be his title rival, at the end of an impressive day for Red Bull.
Ferrari’s Carlos Sainz was third quickest, 0.225secs off the pace.
And Sebastian Vettel was a surprise fourth for Aston Martin, at the home race for team owner Lawrence Stroll, ahead of Fernando Alonso’s Alpine.
Mercedes ‘a disaster’, says Hamilton
Lewis Hamilton described the Mercedes as the “worst I have felt any car here” after another difficult day for the world champions.
The seven-time champion has won the Canadian Grand Prix seven times but he ended the day 13th, with team-mate George Russell seventh as Mercedes continued to experiment with set-up ideas and developments in an attempt to improve their recalcitrant car.
Hamilton said: “[It was] pretty much like every Friday for us, trying lots of different things, an experimental floor on my side, which didn’t work.
“Nothing we do to this car generally seems to work. We are trying different set-ups. Me and George went with much different set-ups to see if one way works and one doesn’t.
“For me it was a disaster. It’s like the car is getting worse, it’s getting more and more unhappy the more we do to it. This is the car for the year and we just have to tough it out and work hard on building a better car for next year.
“One touch of the kerb and the thing goes flying, it’s so stiff and here you need to be able to use the kerbs, it’s very, very tricky. It’s not the Montreal I know and have experienced through my career.
“It is just a monumental fight the whole time to keep it out of the wall. When it bounces – when the car leaves the ground – a lot, and when it lands it grips up, it goes in lots of different directions.
“And so you are just trying to catch a car that jumps, hops, grips, hops, grips. It’s tough. It just keeps you on edge, there were some big hits today but we will raise the car and it doesn’t make a difference.
“We tried loads of things. Those ones don’t work so we have go and try something else. We are way off but it is to be expected of this car.”
Russell, meanwhile, said he was wary of the qualifying pace of Vettel in the Aston Martin and Alpine’s Alonso.
“We’re quite a long way off the pace compared to the front two teams,” Russell said, “but also there’s a couple of guys – Fernando and Sebastian – who look very strong as well, so we have work to do.
“We just need to make sure we qualify ahead of the midfield. I think the race car will put us in the third best team position spot but if we qualify out of position it will be a little bit tricky.”