DEBRIEF: What happened on Day 4 of the Barcelona Shakedown?

The fourth day of the Barcelona Shakedown is now done and dusted, with just Friday remaining for some of the teams to complete their programmes. Others wrapped up their week during Thursday, however, and F1.com has got the lowdown on that and more in our Day 4 debrief…

Which teams and drivers ran?

Amid a cold and cloudy start to Day 4, several cars made an early entrance when the morning session got underway, with Sergio Perez, Kimi Antonelli, Liam Lawson and Lewis Hamilton all heading out for Cadillac, Mercedes, Racing Bulls and Ferrari respectively.

Oscar Piastri went on to join the fray as the morning progressed, making his first appearance of the shakedown for McLaren following the squad’s first run with Lando Norris at the wheel on Wednesday.

Antonelli and Hamilton had clocked up particularly extensive mileage by the lunch break, while Aston Martin – who previously confirmed that they intended to join the action on Thursday – were yet to make an appearance.

Charles Leclerc was the first to emerge as the afternoon got underway, the Monegasque taking over driving duties at Ferrari, while George Russell joined the action for Mercedes, Arvid Lindblad returned for Racing Bulls and Perez put in further laps for Cadillac.

Aston Martin made their debut later in the day, with Lance Stroll heading out on track in the AMR26 – and after further running from Leclerc, Russell, Lindblad and Perez, Day 4 drew to a close at the Circuit de Barcelona-Catalunya.

Who is still to run?

Every team – with the exception of Williams, who will not be participating in the Barcelona Shakedown but have since issued an update on their pre-season testing plans – has now been out on track at the Circuit de Barcelona-Catalunya.

With each squad permitted to run on three days across the five-day event, Mercedes and Racing Bulls have now used their allocated running time, having both spread their programmes across Monday, Wednesday and Thursday.

That means that McLaren, Red Bull, Ferrari, Aston Martin, Haas, Audi, Alpine and Cadillac all have the option to run on Friday, having all used two days so far – Aston Martin aside, who started their running on Thursday.

What have the drivers said?

With Mercedes having now completed their allocated three days in Barcelona, Antonelli felt that the team’s significant lap count was a positive factor, whilst the Italian also spoke positively about the opportunity to learn about the new car during his final morning in the W17.

“I think it was a pretty good shakedown,” Antonelli commented. “We did a lot of laps, so really good mileage for the team. I’m happy because I’m learning quite a lot about the car, and just looking forward to being back in Bahrain.”

Looking ahead to that first pre-season test at the Bahrain International Circuit, the 19-year-old added: “We go there with high confidence and high hopes because it’s been good. Obviously we had our issues during the shakedown, but we were able to fix them and now we can be sure that in Bahrain we can more or less hit the ground running there as well.”

On the other side of the garage, Russell also sounded a positive note about how the shakedown had gone for the Silver Arrows.

“I think it was a very positive test, to be honest, and we had lots of mileage on the car which was the main focus of the test,” the British driver reflected. “The car’s feeling nice to drive, no major issues, no porpoising which is pretty good news for all of us, so all in all a decent few days.”

Despite this, Russell added: “We’re in a reasonably good place, but I’m sure things are going to change a lot between now and the next Bahrain test, and then I’m sure people are going to be bringing upgrades to the car, so still very much early days.”

Racing Bulls also wrapped up their running on Thursday and, following his final run at the wheel before handing over to Lindblad for the afternoon, Lawson said: “We just keep learning. We’re making big gains, but so is everybody else. Very, very different cars, but [we’re] in a much better place than we were on Monday which is the main thing. We just need to keep learning and improving the car.”

In terms of whether the team are at the point they wanted to be by this stage of the shakedown, Lawson continued: “I think yeah, in terms of mileage, yes – we’ve honestly had a pretty strong test in terms of reliability, so that’s been a box ticked. In terms of expectations, it’s very hard obviously – we don’t know where anybody else is.

“That’ll still be quite unknown for a while, but the main thing is we’re getting the laps down that we want to and learning what we need to about our car.”

After taking over for the squad’s final session of their programme, Lindblad said of the day: “It was good. It wasn’t the smoothest, but overall we went through the programme, we did some good testing, we’ve learned a lot about the car as well.

“So [I’m] thankful for the team for this test, and now just looking forward to doing some work before Bahrain in the sim and then getting back on track in a couple of weeks.”

Over at Ferrari, Hamilton admitted that he was pleased to gain some mileage in the dry, having experienced wet conditions during his previous run on Tuesday.

“It was great to be able to get some running and understand the tyres,” the seven-time World Champion explained. “We did the C2 and the C1. It’s so cold that the tyres are not really working so much, but we got through our programme and [got] a bit of an understanding of where the car is at and where we need to improve.”

Like others, Hamilton was encouraged by the lap count that the Scuderia have amassed so far in Barcelona, with the Briton labelling his mileage during Thursday morning as “amazing”.

“Last year we had a worse start to testing, so this is actually – considering it’s a completely new band of rules – it’s better than we’ve experienced in the past, so I’m really hopeful that continues,” said Hamilton.

Leclerc was also glad to experience a dry track when he got behind the wheel of the SF-26 later on Thursday, summarising after the session: “It was nice. It’s super interesting, it’s kind of the first day for me in the car in normal conditions, so a lot to learn, a lot to discover, and it’s a very different car to what we’ve been driving since I arrived in Formula 1.

“I take that as a challenge and I actually quite like that everything is new, and there might be an opportunity for us drivers to think outside the box. It’s been an interesting day, no problems again, quite a lot of laps, so that’s good.”

Ahead of the team’s final day of running on Friday, Leclerc admitted: “The checklist is massive still, so there are still many, many things that we want to test and try differently, whether it’s set-up on the car, some different things or some approaches that we have with these new systems. There are many, many, many things, but we are on track of checking all of those, which is a good thing. I just hope it stays that way.”

As McLaren embarked on the second day of their programme, Piastri shared his thoughts following his first shakedown laps at the wheel of the MCL40.

“It was nice to be back out, and especially in a new car,” the Australian conceded. “A lot of new challenges for us this year up and down the grid, so it’s nice to get stuck into some of them.

“Unfortunately a few issues today. We had a fuel systems issue, which cut our day a bit short, but I know the team’s working really hard to get that fixed and get us back out for as many laps as we can tomorrow.”

Reflecting further on what the papaya squad have achieved so far with their programme, Piastri continued: “Definitely the first few things are just trying to iron out all these bugs, find the problems. They’re all completely different cars, completely different engines to what we’ve had for the last three or four years, so that’s part of what this test is about.

“I think we’ve already identified a few things we can try and improve on the car to make it feel a bit nicer. They’re all going to be different to what we’ve had so, yeah, just trying to find all the bugs, all the problems, and then try and make the car faster.”

Following Cadillac’s second day on track, Perez felt that the squad’s running had improved on their first outing on Monday, with the Mexican commenting: “A much better day. We got a lot of running, a lot of information. Still finding a few issues out there, which is great – it was all about that today.

“I think we are improving pretty much every run. It’s been a positive day, so hopefully tomorrow with Valtteri [Bottas] we can have another positive.”

When asked if he is feeling more comfortable in the car with each lap, Perez responded: “Yeah, I do. We’re obviously starting to explore the car, the set-up, directions we want to be taking, so I think it’s starting well.”

Aston Martin, meanwhile, gained their first laps of the shakedown during Thursday afternoon, and Stroll admitted that it “felt good” to be back on track again.

“Nice to be back in the car after a few weeks off,” the Canadian said. “Everyone did a good job in getting the car ready today. It was a long day for all the mechanics and everyone in the team, pushing flat-out to get the car ready, so we got a few laps in at the end of the day and it was feeling good.”

With the team embarking on the first season of their partnership with Honda, Stroll added on the 2026 car: “[It’s] a big project, very complex. A lot of hours have gone into this machine, so it was nice to get behind the wheel and getting used to the new Honda power unit and these new cars. It’s exciting.”

What’s next?

There is now just one day remaining of the Barcelona Shakedown, and – as mentioned above – eight teams still have the option to run during Day 5 on Friday.

After that, the next opportunity for the field to take to the track will be at the first pre-season test, which is set to be held at the Bahrain International Circuit from February 11-13 followed by a second test at the same venue across February 18-20.