George Russell and Mercedes blew away their F1 rivals on day four (Thursday, January 29) of the Barcelona shakedown.
From day one there was hype surrounding Mercedes, and they have only continued this trend on their final day of the shakedown, having completed their three permitted days of testing (on Monday, Wednesday and Thursday).
On Thursday, Russell drove the W17 in the afternoon and (with the caveat all lap times are unofficial) set the first time in the 1:16s, bettering the previous quickest time of the week set by team-mate Kimi Antonelli, 1:17.081, in the morning.
Reportedly, the plan for the afternoon was to attempt some qualifying runs, which may explain the pace deficit to Mercedes and their rival teams somewhat.
More than the times, however, Mercedes have also impressed with their reliability and clocked 388 laps (over all days of testing) by lunchtime on Thursday, with Antonelli confirming he had completed '90 laps' alone that morning.
Speaking after day four's running, Antonelli said: "I think it was a pretty good shakedown. We did a lot of laps, 90 today, so really good mileage for the team.
"I’m happy because I’ve been learning quite a lot about the car, and just looking forward to being back in Bahrain.
"We kept it very similar to yesterday because the main goal was still to do long running, so definitely we tried different modes just to have a better understanding of the battery and how it behaves.
"Today was a bit more focused on soft tyres, also long running with soft tyres, just to see how the car was responding and especially how the power unit was responding with the high speed into the corners. It was very interesting."
So, what about the rest of the teams?
Elsewhere, it was Aston Martin's first day on track in Barcelona, after it was announced they would only be completing two days of the shakedown. The F1 community waited with baited breath for a glimpse of the AMR26, and it looked as if they were not going to run at all, until Lance Stroll took to the track for the final 45 minutes on Thursday.
Ferrari and Lewis Hamilton also enjoyed extensive running on Thursday morning, and despite an early pirouette, the seven-time champion managed to complete 85 laps in the SF-26.
He said to the media after his running: "When you come to the test, you always want to get a lot of mileage. Today, I did 85 laps in the morning, which is amazing. That’s really down to all the people in the factory who have done such a great job to make sure that the car, so far, is really reliable.
"Last year we had a worst start to testing. So, considering this is a completely new band of rules, it’s better than we’ve experienced in the past, so I’m really hopeful that continues."
There was so sign of Red Bull and Max Verstappen on Thursday, who were forced to sit out the shakedown again, after Isack Hadjar's crash on Tuesday caused damage to the RB22.
The team are currently awaiting parts from Milton Keynes to help them return to the track on Friday. Currently, Verstappen has only completed 27 laps, in wet conditions, so gaining more mileage on Friday will be crucial.
Oscar Piastri also enjoyed his first time out on track in the MCL40, taking over from Lando Norris' driving duties on Wednesday. Neither driver has managed to match the lofty heights of Mercedes, however.
Thursday marked the final day of the Barcelona shakedown for Mercedes and Racing Bulls. Meanwhile McLaren, Ferrari, Aston Martin, Red Bull, Alpine, Haas, Audi and Cadillac can all complete their final day of testing on Friday, barring any last minute issues preventing them from leaving the garage.
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What is a shakedown?
A shakedown refers to the first time teams can properly run their cars on track, like a pre-season health check.
Teams get the chance to test out all of the new design features on their new cars without limitations, with no maximum limit put on the number of laps they are allowed to do each day.
The private shakedown means the press do not have access, and only a small crew are admitted to film content for teams and drivers.
Nevertheless, Sky Sports F1 will be on hand to guide viewers through the Barcelona shakedown, with a testing highlights show broadcast at 9pm (GMT) every night of the week of the test. The show will then be available on Sky F1's official YouTube channel.
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