Jenson Button, McLarenJenson Button reckons it was a mistake to run at all in Q3 of Canadian Grand Prix qualifying, as he will now have to start the Montreal race on slightly worn soft tires.

The McLaren driver used all his super-softs just to reach the top 10 session, and was the only man to run softs in Q3, leaving him 10th on the grid.

"We wanted to start the race on the prime tire. 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.

"We were going to be P10 on the option tire and thought we'd give it a go on the prime and start the race on a prime, but maybe we shouldn't have put five laps on it."

Button was pessimistic about his chances of being able to use his alternate tire choice to make progress on Sunday.

"I don't really think there are any risks with strategy. Especially here," he said. "It's going to be a one or a two-stop, and I think most people will be two stopping. Obviously, I'll be starting on a different tire to the front nine, but I'll be starting on the same tire as everyone behind me. At least we're at the front of that pack, I suppose."

He also doubts that he will be able to do a great deal of overtaking.

"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, I feel," Button conceded.

The Briton lost a large amount of Friday practice mileage to an oil leak and related gearbox issue, but said Saturday's result was more a continuation of his recent qualifying strife than a consequent of practice issues.

"I don't even know if it would have been any better if we'd had all of Friday, looking at the previous two [races]..." he said.

Button admitted that he feels no closer to solving the qualifying issues that have now slowed him on Saturday for three successive races.

"I haven't got a clue, and I'd like to know because it would make life a lot easier," Button replied when asked if he knew what was wrong with his qualifying form. You don't have three bad qualifying sessions and understand what's going wrong.

"The first three qualifying sessions of the year were good – I had two seconds and a fourth. Now suddenly I'm only just inside the top 10. Don't know... But hopefully we'll solve it soon."