It's early days still but Lewis Hamilton is impressed with what he's seen so far from Red Bull and believes Mercedes' arch-rival is "a different animal" this season.
Max Verstappen concluded pre-season testing in Bahrain at the top of the timesheet on Sunday.
The performance, coupled with Red Bull's flawless reliability and Sergio Perez' equally strong showing, validated Red Bull's solid initial form and bodes well for the Milton Keynes-based outfit's prospects for the opening round of the 2021 F1 season at Sakhir in two weeks.
"They’re looking strong," said Hamilton. "They’ve had some really good running.
"They’re going to be a different machine or animal this year with, I think, a really good, strong line-up for two drivers and a really good car.
"Having seen them winning the last race you can only assume they’re going to be right there if not at the front, at the first race. It’s going to be a great, long battle with them through the year."
Red Bull's strong and stable display in Bahrain contrasted with the reliability and handling issues that impacted Mercedes' W12.
However, the German outfit made progress on the final day of running in Bahrain, and Valtteri Bottas is hopeful the team will further improve its 2021 challenger during the run-up to the first race.
"It’s so hard to say at the moment where we are, where other teams are," the Finn commented.
"Obviously we don’t know their [Red Bull's] run programme, what engine modes they’re running and what fuel load – but I have a feeling it’s going to be close. That’s all I can say.
"I feel like we made a decent recovery. I can’t say that we fully achieved the mileage that we wanted for the three days but actually, not that far off.
"Yesterday we made 95% out of it and today 100%. We had a really solid day with a good amount of laps and quality laps and quality tests so considering what happened on day one, [given] how day two and three went I’m pleased.
"But now it’s time to turn that data into performance somehow in the next two weeks before the race."
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