Max Verstappen doubts Red Bull Racing will have the ability to win against arch rivals Mercedes and Ferrari in the second leg of the F1 season.

The Milton Keynes-based outfit was a favourite to beat Mercedes when the season kicked off in Melbourne back in March, but correlation issues hampered the performance of its RB13 early on.

Successive upgrades have highly improved its new-spec car but Verstappen believes Red Bull will still likely remain outside the Mercedes/Ferrari two-way battle.

"For us, on tracks with not too many straights I think we are reasonably close, so I think [Red Bull is] around three-tenths [down], more or less," says Verstappen.

"But then of course when you get a few straights in the track I think we're a bit further away.

"I don't know what to expect for the upcoming races but of course it will be quite tough for us to really compete against them.

"I expect in Spa Mercedes will be again very strong because in general their power unit is still the best in the whole field, but it's very close [between Mercedes and Ferrari]."

The Dutch teenager also believes the team's relative performance deficit to the front-runners could be sustained by the lack of development of its Renault power unit.

"We'll keep developing, but the other teams do [as well]; we have to make sure that we do it a little faster and of course better," he commented.

"I think from the engine side there is not much coming compared to the other teams where there is still development on both sides [chassis and engine].

"So we have to make sure our car is definitely going in the right direction."

Asked about is commitment to Red Bull Racing given the outfit's current under-performance, Verstappen insisted he had no desire to seek out greener pastures, for now.

But that could change if his team fails to return to the winner's circle in the longer term.

"I've always said that there's no reason to leave when I have a competitive car," said the teenager.

"At the moment we are not there where I want to be, but that doesn't mean you have to give up straight away. You have to work hard.

"But after two, three years without improving, that would be a different story. We are working hard to improve but after next year we will see what happens in the future."

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