The Canadian Grand Prix was last weekend and it's safe to say that it didn't quite go to plan for Lewis Hamilton and Mercedes.

Teammate Valtteri Bottas did manage to pick up second place, although he can't have been best pleased with that either considering it was his fourth of the season while he's still yet to win one.

But Hamilton was the one who really had a tough time - his fifth-place finish was his lowest of the season and only the second time he's failed to podium.

That result meant the reigning champion gave up top spot in the standings to Ferrari's Sebastian Vettel, although that was somewhat expected.

Mercedes went into the race with a disadvantage; whereas other teams debuted new-spec engines, Hamilton and Bottas were both relying on engines that have served since the opening race in Melbourne.

New rules mean that drivers are only allowed to use three engines over the season's 21 races and so timing is considered important - as well as reliability.

But Hamilton is worried that these new rules are pushing Formula One in the wrong direction.

"I hope they don't go to two engines next year because it's just going to get ridiculous," said Hamilton. "It was definitely a bit more fun when you had more engines I would say.

"The fact that a season can sway through reliability, I don't think anyone wants to see that, I don't think anyone wants to be cheated of that - you want actual true performance.

"The sport is going in the wrong direction in my opinion; I have so many different opinions about it.

"They needed to fricking change these bleeding engines to save costs and then they spend more to produce it."

The hope for Mercedes is that they can fit the new engine and get it operational in time for the French Grand Prix in Le Castellet later this month.

Something certainly needs to be done soon - if the last two results are anything to go by, Vettel might be ready to pull away from Hamilton this year.