Hamilton and Bottas hint at further Mercedes engine upgrade delay

Mercedes had planned to introduce the new spec across all six of its cars in Canada, but the introduction was delayed after last minute reliability issues on the dyno.

Since then it has made modifications, and continued dyno running, with a final decision on its Paul Ricard use potentially being made last-minute.

One possible scenario is that Mercedes could gain a further day of dyno running by using its old engines on track on Friday, and then switch to the new spec for Saturday if its Brixworth engine base gives the go-ahead.

If not then Mercedes may have to deploy fresh examples of the old spec on Saturday, and those engines will in theory then have to do seven race weekends.

If the new spec is proven within the next few races then the 'fresh old' spec could then be saved and deployed at venues where power is less important.

Asked about the options, Hamilton replied: "At the moment, I don't know. I think I might have one of my new engines out of my three, which is good enough.

"The engine that we've used for the first seven races has been a great engine.

"A fresher, newer version of that is going to be great, and have more power than the [high mileage] one I raced in the last race, obviously. And so I personally am not concerned.

"Tomorrow or the next couple of days we might have a better understanding of where we stand with that."

Hamilton said he had been in constant contact with Mercedes engine chief Andy Cowell.

"Coming into this weekend, I've been on the phone to Andy this week, last week and into this week, and I have absolute full confidence in him and the guys," he said.

Bottas hinted that the engine decision could be taken after Friday practice.

"For sure we need to take some kind of new engine," he said. "This one is seven races old, and we are very much wanting to run the new one, but we need to confirm tomorrow if we can or not.

"Any gain we can get - including a new engine - will be very important if we want to win the title. We all hope we can get the new one. At the moment that is our plan but we just need to confirm.

"I trust that things are being improved since two weeks ago with the new engine. If we decide to run it, for sure we are confident to run it 100%."

Bottas conceded that having to stick with the older specification for seven races would be a blow.

"This is a big gain and we really need it," he said.