Montreal: Lewis Hamilton admitted his surprise at second place on the grid after struggling for grip during qualifying for Sunday's Canadian Grand Prix. (Agencies)
The 27-year-old McLaren driver, who dominated the opening day in Montreal, found it difficult to adjust to Saturday's warmer track temperatures at the Gilles Villeneuve circuit and wound up over a third of a second slower than pole-taker German Sebastian Vettel of Red Bull.
"It was definitely a bit harder for us today," he said. "We struggled working with the tyres, we were trying really hard to get the tyres to switch on, but fortunately we had a new set in Q3 and managed to get through.
"I'm happy with performance, and surprised to see us on the front row, but we will be trying as hard as we can tomorrow."
The 2008 champion, still chasing his first win of the season, admitted he had concerns about his car's tyre wear during the race.
"Long runs seemed to be OK but now it's hotter it will change things and it will be tough," he said.
"We'll try to do the best job we can and maximise all we can do. I am looking forward to it.
"Of course I want to win but these guys are phenomenally quick at the moment," he said. "Not sure if we have the pace but we will wait and see tomorrow."
In contrast, his McLaren team-mate and English compatriot Jenson Button's weekend went from bad to worse after another poor qualifying performance meant he had to settle for tenth place on the grid.
The 2009 champion admitted he regretted running at all in the final session as it removed the option to change tyres before the race.
"We wanted to start the race on the prime tyre. To be fair, looking at it now, we shouldn't have actually bothered running it because it was going to be tricky to beat anyone on it," said Button.
The 32-year-old, who made 28 overtakes before winning last year's Canada race, admitted he was not feeling so positive ahead of Sunday's race having not spent much time on the track because of a problem with his car on Friday.
He said: "The scary bit is at the moment I don't feel that good under braking, so it's going to be difficult to make any manoeuvres tomorrow."
Montreal: Lewis Hamilton admitted his surprise at second place on the grid after struggling for grip during qualifying for Sunday's Canadian Grand Prix.