There's a bit of a headache for Toto Wolff as Mercedes think things through before qualifying starts at 19:00 BST. Everyone assumed that, once they got on to the hypersoft tyres - the softest in the Pirelli range - that they would race away. That has not happened. So what was the thinking behind not using the relatively new hypersofts at all on Friday? Over to Andrew Benson for analysis...

Reuben Graham: Really disappointed with McLaren. Proof, if it were needed, that Honda weren't wholly to blame for their lack of pace. What's the issue though? How do they fix it? Poor Alonso especially watching Red Bull doing so well with the same engine.

Yes, Fernando Alonso rather slipped away during that session, finishing 13th.

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Mercedes boss Toto Wolff, speaking to Sky Sports: "It's going to be an interesting one because we have used the hypersofts for the first time but we have work to do. We did not get the jumps we wanted and we are not looking good through the hairpin. We have to look at why that is.

"I think the pace is in the car but Vertsappen and Ferarri have the pace as well. We will see where it gets us in the end but I can't judge."

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Andrew Benson
BBC Sport’s chief F1 writer

Max Verstappen set the pace for Red Bull in an intensely competitive final practice session at the Canadian Grand Prix.

Just 0.051 seconds covered the first three drivers, with the Dutchman ahead of Ferrari drivers Sebastian Vettel and Kimi Raikkonen.

Vettel was just 0.02secs quicker than his team-mate.

Lewis Hamilton was fourth, just 0.107secs off the pace, but there are questions about whether a decision to choose fewer of the fastest hypersoft tyres this weekend will hamper his Mercedes team.

Hamilton and team-mate Valtteri Bottas did not run the hypersofts at all on Friday, and had only one set to run in the final practice session because they have two fewer sets than any other team.

The expectation is that Mercedes - and perhaps Ferrari and Red Bull as well - will try to make it through second qualifying using the harder ultrasoft tyre, thus allowing them to use it for the start of the race.

But they will need the hypersofts for the battle for pole position in the final qualifying session.

Red Bull’s Daniel Ricciardo and Bottas brought up the rear of the big six, with the midfield battle headed by Force India’s Sergio Perez, from Renault’s Nico Hulkenberg, Haas’ Romain Grosjean and McLaren’s Stoffel Vandoorne.

Fernando Alonso in the second McLaren did not have a good session and was only 13th, 0.191secs slower than Vandoorne, who the Spaniard has out-qualified in every race so far this season.

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Stand by for your instant report, courtesy of our chief F1 writer Andrew Benson...

Bishnu Prasad Panda: Want to make F1 exciting? Don't get the grid girls back, don't have to have screaming engines, don't need ease of overtaking. Just need Max Verstappan racing without trouble.

Max Verstappen's session is over early - seems as though Red Bull are taking no chances. They don't want a repeat of his final practice crash in Monaco.

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Sreejay S: Verstappen is that guy in the mirror on the highway, dipping in and out of the lanes, horns blaring and light flashing, who we prefer to let go. Just need another like him in #F1 to get it all messed up. The talent is hidden by his disregard for other drivers.

Five minutes left. Verstappen is on a practice hat-trick, as it stands.

Mercedes' two cars are back in the garage. Their rear tyres are not looking great - there's a serious question over their effectiveness on the hypersofts here.

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Grosjean now alerts the Haas garage to what sounds like a minor engine issue. Not stray groundhog fur jammed in it, I hope.

Keith Murphy: From the looks of FP3 we are in for one hell of a quali later and a mental race tomorrow.

Final 10 minutes of third practice. It feels as if it's between the current top four for first spot.

Further back, Romain Grosjean, seemingly over his Friday groundhog collision calamity, is briefly up to seventh - although Nico Hulkenberg has just overtaken him.

I'll give you two guesses as to which two drivers are in the bottom two places.

Wow! Max Verstappen suddenly comes through and whizzes into top spot. The top four - Verstappen, Vettel, Raikkonen and Hamilton - are just over 0.1 seconds apart. Anyone's game!

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But Hamilton loses time on the final sector, coming into the Turn 10 hairpin, and has to settle for third - for now. Ferrari still lead the way with Vettel and Raikkonen.

Not a great deal to get excited about for Hamilton on that first lap on the hypersofts... The second, though, looks a lot more promising...

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Vettel comes into the pits, possibly for a slight front wing adjustment, and is straight back out again.

Sebastian Vettel, on the Ferrari radio, tells his team that he's happy with what he's seen on the hypersoft tyres. Lewis Hamilton finally looks ready to go on the hypersofts. So let's see what he can do...

Kimi Raikkonen is briefly back on top - quickly replaced by Sebastian Vettel, a Ferrari one-two. A worry for Mercedes, as Valtteri Bottas is only able to climb to fourth on the hypersofts. Lewis Hamilton is still in the garage - we're told he's still not happy with the car. Just 20 minutes left, and Hamilton has not yet been out on the hypersofts. Daniel Ricciardo is now third.

Out goes Bottas on the hypersofts... Lewis Hamilton is still having his front brakes looked at, we're told. Sebastian Vettel is out on the hypersofts, but there's a lot of traffic out there.

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