Lewis Hamilton: "I guess I'd have to say I'm not entirely happy with how this afternoon went. Today, in general, the track has been incredibly difficult to drive. It's very hard to switch the tyres on and get heat into them - it's so slippery, it's like driving on an ice rink. It's such a huge difference from when we were last here.

"We're not pulling away down the straights and we've got quite a bit of bottoming - but we can improve in those areas. We're going to have a big debrief this evening and work out where we want to go with the car for tomorrow.

"The graining on the Option tyre made things difficult too - but I think everybody had a similar experience out there, except maybe the Red Bulls. I don't think you'll be seeing a long first stint on the Option tyre on Sunday, that's for sure."

Jenson Button: "We need to find out what changed from this morning to this afternoon. I was happy with the car in P1, but less so in P2. Certainly, we struggled with the balance instability under braking and corner entry during P2.

"It was tough on the long runs - the tyres didn't last long. I ran with the Option tyre at the end of the session for just a couple of laps, and it grained so much that I had to put the Prime on, where I was two or three seconds quicker than the cars still running Options. Still, I then started experiencing graining as well, so we have a few tyre issues - but then again I think almost everybody is struggling with tyre issues here. It could be a pretty interesting race.

"We're possibly a little bit too quick along the straights, too. Maybe we're not running enough downforce, but we'll look at that. But we've got a lot of info from today's running, so we'll go away now and work out what we need to do for tomorrow."

Martin Whitmarsh, Team principal: "The Circuit Gilles Villeneuve is a uniquely challenging track, which never fails to throw up tricky conditions, abnormal circumstances and unpredictable outcomes. This morning, we were able quickly to establish a competitive baseline with both cars. This afternoon, however, we found it difficult to refine that advantage, particularly when we switched from Prime to Option tyres. In so doing, we lost not only balance but also found that the Options were graining extremely quickly.

"Nonetheless, we've amassed a significant amount of data from today's running - and our task now is therefore to sit down and sift through it with absolute thoroughness in order to hit the ground running tomorrow morning.

"We're still convinced that our basic package should be quick around here - it's just a matter of adapting it to suit the prevailing weather and circuit conditions, which today proved tougher than we'd initially anticipated."

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