George Russell is most impressed with Alfa Romeo after assessing Williams’ main rivals following Formula 1 pre-season testing in Bahrain.

Alfa Romeo completed 422 laps across the three days of testing - joint with AlphaTauri as the most laps completed by a single team.

Kimi Raikkonen enjoyed a strong final day in the car as he completed 166 laps in the C41 on his way to fourth fastest overall on the final day.

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Williams was often battling Haas and Alfa Romeo in 2020, however, Russell believes Alfa has taken a step forward in 2021 and noted Raikkonen's impressive turn of pace on day three in Bahrain.

“Yeah, Kimi looked very, very fast today, Russell said after day three of pre-season testing in Bahrain. “I have to give him credit, I need to look deeper into the data but I would say at the moment they look like the most surprising team. 

“I can't honestly tell you where I think we are in comparison because I've only been out with the car for an hour and a half and I've been deep in debriefs until literally half past eight  But on the face of things, Kimi looked very very fast today.”

McLaren’s Lando Norris believes Mercedes is on the back foot going into the season after it struggled for mileage, while when on track, the W12 looked tricky to drive.

Russell - who is a Mercedes junior driver - remains confident Mercedes will turn things around.

“To be honest, no,” Russell added. At the moment I'm just focused on us. I've not really looked at the guys at the top. You know, I've asked them how it's going.  But they are Mercedes, They are going to be fine. I am pretty confident about that.”