Renault Q3 weakness puts Red Bull drivers under 'too much pressure'

The team has not qualified higher than fourth so far in the 2018 F1 season.

At last weekend's Spanish Grand Prix, Verstappen and Ricciardo started only fifth and sixth but Verstappen finished on the podium and Ricciardo set fastest lap.

Horner is keen to find more performance from Renault.

"The key thing for us is trying to increase competitiveness on a Saturday afternoon, because grid position is so important," he said.

"It puts too much pressure on the drivers in Q3, because they're having to find even more performance because we don't have the ability to go with our rivals' engine modes.

"Hopefully around Montreal time, there is the next engine introduction. We are hoping for a performance increase."

Asked if he expected that performance upgrade for Canada next month to be significant, Horner replied: "That is a question for Renault".

He believes the Red Bull RB14 is an even better race car after updates added for the Spanish GP, where he felt his cars' Sunday performance was on a par with dominant winner Lewis Hamilton's Mercedes.

"Unfortunately the damage done on a Saturday compromises your race at a track like [Barcelona] on a Sunday," Horner added.

"Looking at the pace of the car it looked on a par with what Lewis could do, particularly in the second half of the race.

"The problem is when you are caught up in traffic you are damaging the car, when you are clean air it's a lot easier to manage.

"[Daniel] was coming through the backmarkers and we actually turned the engine down.

"The encouraging thing is the upgrades have all worked reasonably well and once again we've demonstrated we got a competitive car on a Sunday afternoon.

"We had a good car all year. We've had good strategy, the race team and the pitstops have been excellent.

"We'll keep doing what we do and hopefully the results will get stronger and stronger."

Third place in Spain, despite wing damage from a brush with Lance Stroll's Williams, was Verstappen's first podium of a so-far difficult 2018 season.

"It's good to get his first podium on the board for him, as a confidence-booster," said Horner.

"It kickstarts his season. For any sportsman, when you've had a bit of a rough patch, it's always good to get a result in and get under way."