Formula 1 Canadian GP: Mercedes will be hard to beat

Ricciardo's Red Bull team-mate Max Verstappen topped both sessions in Montreal, while Mercedes ended FP2 only fourth and sixth quickest with Lewis Hamilton and Valtteri Bottas.

But while Hamilton was 0.579s off the pace, neither he nor Bottas ran the hypersoft compound in FP2, as the team opted to save its slim allocation for Saturday's running.

Ricciardo admitted Mercedes' pace on the harder compounds was an ominous sign, hinting that his Red Bull team could find itself consigned to battling Ferrari for best of the rest.

"I would say that Mercedes' pace was really fast today," Ricciardo said. "Even on the harder tyre, they were still doing pretty good lap times.

"I think they'll be at this stage hard to beat, but I think we can still improve the car a lot, do more laps, learn a bit more and I think we'll be OK.

"I guess the fight will be with Ferrari, too early to really know, but I'm sure Mercedes will be really fast tomorrow afternoon."

Ricciardo's running was disrupted by electrical issues that kept him sidelined for much of FP2, the Aussie believing these to be caused by the need to configure the new-spec engine that Renault introduced in Canada.

"We had some problems this morning, they tried to fix it during lunch, but it didn't improve," he explained.

"We have the B-spec engine this weekend, the upgrade, and I think just configurating a few things on that, we're not necessarily aligned, so we just had to go through a little bit of trial and error.

"A little bit obviously frustrating not to get many laps, but the problem doesn't seem dramatic."

Ricciardo took encouragement from the pace of Verstappen, who said "straight away the set-up was right" on his RB14.

The Dutchman stressed, however, that he had "no idea so far" of the magnitude the performance gains from the new Renault specification.

"It's still difficult to say," he said, "because you're not going flat out on the engine yet. I think I can tell you tomorrow."

Asked whether his Friday clean sweep meant pole position could be on the cards, Verstappen replied: "In terms of pole position, I think Mercedes will be very strong again. Our car works well, but whether that will be enough in Q3, I don't know."