Lewis Hamilton cracked Red Bull's run of qualifying dominance on Saturday by securing pole position for the Canadian grand prix.

But the McLaren driver was using a different tyre in the decisive Q3 segment -- the fragile 'option' or softer compound, as opposed to the harder 'prime' fitted to the next-best Red Bulls of Mark Webber and Sebastian Vettel.

The three prior practice sessions at the Circuit Gilles Villeneuve proved that Bridgestone's products are struggling this weekend; particularly the option.

Red Bull team boss Christian Horner said earlier in Montreal that it had fallen apart "like cheese" in Canada, moving some to surmise that by qualifying with it on Saturday, McLaren is gambling on an early safety car.

9 of the previous 12 Canadian grands prix have seen the safety car appear.

"We would hope for an early-ish safety car, but I think the quickest way to run the race anyway is to start on the soft tyre, run a short (first) stint, and run on the prime for most of the race.

"If there's a safety car it's a very strong strategy," team boss Martin Whitmarsh told the BBC after qualifying.

However, Vettel told reporters that he thinks Red Bull is beginning the race on the "right tyre", because the softer one lasts only "a couple of laps".

Hamilton acknowledged that the option "goes off quite quickly" but raised the high "possibility of a safety car".

The 25-year-old Briton had to be delivered to parc ferme in an FIA car, after his engineer told him to stop on the circuit on the in-lap so there is enough fuel left in the tank for a mandatory fuel sample.

"The FIA don't take kindly to you not having enough fuel to get into the pits at the end of the lap -- they'll be taking a look at that," predicted BBC commentator Martin Brundle.

Ferrari's Fernando Alonso is fourth ahead of the second McLaren of Jenson Button, while Vitantonio Liuzzi qualified sixth in what Brundle describes as a "career saving performance".

Pos No Driver Team Q1 Q2 Q3 Laps
1 2 Lewis Hamilton McLaren-Mercedes 1:15.889 1:15.528 1:15.105 20
2 6 Mark Webber RBR-Renault 1:16.423 1:15.692 1:15.373 21
3 5 Sebastian Vettel RBR-Renault 1:16.129 1:15.556 1:15.420 24
4 8 Fernando Alonso Ferrari 1:16.171 1:15.597 1:15.435 24
5 1 Jenson Button McLaren-Mercedes 1:16.371 1:15.742 1:15.520 24
6 15 Vitantonio Liuzzi Force India-Mercedes 1:17.086 1:16.171 1:15.648 22
7 7 Felipe Massa Ferrari 1:16.673 1:16.314 1:15.688 23
8 11 Robert Kubica Renault 1:16.370 1:15.682 1:15.715 21
9 14 Adrian Sutil Force India-Mercedes 1:16.495 1:16.295 1:15.881 21
10 4 Nico Rosberg Mercedes GP 1:16.350 1:16.001 1:16.071 20
11 9 Rubens Barrichello Williams-Cosworth 1:16.880 1:16.434   22
12 10 Nico Hulkenberg Williams-Cosworth 1:16.770 1:16.438   20
13 3 Michael Schumacher Mercedes GP 1:16.598 1:16.492   16
14 12 Vitaly Petrov Renault 1:16.569 1:16.844   21
15 16 Sebastien Buemi STR-Ferrari 1:17.356 1:16.928   16
16 17 Jaime Alguersuari STR-Ferrari 1:17.027 1:17.029   17
17 22 Pedro de la Rosa BMW Sauber-Ferrari 1:17.611 1:17.384   19
18 23 Kamui Kobayashi BMW Sauber-Ferrari 1:18.019     10
19 19 Heikki Kovalainen Lotus-Cosworth 1:18.237     12
20 18 Jarno Trulli Lotus-Cosworth 1:18.698     11
21 24 Timo Glock Virgin-Cosworth 1:18.941     12
22 21 Bruno Senna HRT-Cosworth 1:19.484     10
23 25 Lucas di Grassi Virgin-Cosworth 1:19.675     12
24 20 Karun Chandhok HRT-Cosworth 1:27.757     3

Be part of something big