F1 rivals 'fighting for second' behind Verstappen in Bahrain
Both Ferrari's Charles Leclerc and Mercedes' George Russell said the defending champion's team had shown they had a distinct performance advantage in last week's three-day test.
"It's clear, they've had a strong start and both Red Bull and Max seem to be very strong," said Leclerc, who finished second in last year's title race behind the flying Dutchman.
"Yes, it's only testing, so it's difficult to quantify by how much, but it seems like they are a bit in front compared to us. So, we've got some work to do.
"It's only the beginning but the goal for us is definitely to go one better."
Russell and his Mercedes team-mate seven-time champion Lewis Hamilton were both underwhelmed by their new car's performance in relation to the fresh Red Bull, but retained optimism and determination.
"It probably wasn't the smoothest three days we could have hoped for, but I think the lessons we learned from the test," Russell said.
"Those learnings, the findings we found... I think is going to put us in better stead for this weekend."
"But I think it's definitely fair to say Red Bull are in a bit of a league of their own here in Bahrain. I think it'll probably be a nice fight for second place, probably between Ferrari and Aston Martin."
Aston Martin's newly-signed two-time world champion Fernando Alonso played down any hopes of a podium finish despite his own strong showing in the test.
He told reporters that the top three teams remained beyond the reach of the rest of the field and that he did not expect to be troubling them this weekend when he welcomes back teammate Lance Stroll, who recovered from injuries in a training cycling accident.
Verstappen continued to keep a relatively low profile ahead of the new season, in which he hopes to claim a third consecutive drivers' title.
"We had three really good days," he said of the test.
"I think also just in general, the progress we made over the winter was very good. We have to, of course, show it this weekend, but not only this weekend."
"From there on, you continue to develop and every track is also a bit different in terms of behaviour of the car, but, yeah, the test days were good for us."
He said the team's new RB19 car was an improvement "everywhere" over its predecessor, adding that it was "nice (to drive) and well-balanced."
He said Red Bull had adapted well to rule changes that raise the edges of the cars' floors.
"Every team, of course, has lost a bit of performance with the floor, but you always try to gain that back in a way. So, you have to find a bit of a new balance with the car, but it's been good for us. So far."
