F1 Bahrain pre-season testing live commentary and updates - day 4

And with that, we shall leave it there! So thanks for following along and we shall see you tomorrow.

Russell on top

As you can see, not only did George set the fastest lap on Wednesday, but he also completed the most mileage with 76 tours of the Bahrain track.

George Russell, Mercedes

Photo by: Sam Bloxham / LAT Images via Getty Images

Here is a full breakdown from today with Max Verstappen being the only driver not to feature:

Nah in all seriousness, it seemed like a relatively smooth practice start - though obviously total different when the pressure isn't on and drivers aren't going at full speed. 

It's a brilliant start from Piastri, but a slow getaway from Lawson who drops into third behind Sainz.

Drivers are lining up into their grid boxes for race start and we are now go, go, go! 

The atmosphere is tense, fans are on the edge of their seats, awaiting the start of this Bahrain GP with the formation lap underway. Piastri is on pole, but can he hold off the Racing Bulls of Lawson into T1?

With these system checks happening, let me once again refer you to an earlier article about race start procedures...

'aerobalance' asking about brakes on these 2026 cars. The front is hydraulic while the rear is brake-by-wire. 

Testing 1, 2, 3

There's 14 minutes left on the clock, but this is pretty much the final four minutes of running as there'll be various system checks in the last 10. 

This includes starting off with a VSC ahead of a red flag before two formation laps follow, in which cars will then line up on the grid for a simulated race start. 

Once all cars are in position, a new Pre-Start Warning will begin: all grid panels will flash blue for five seconds. After the blue warning ends, the usual start sequence will begin.

As we now approach the final 20 minutes, Lindblad still has the highest lap count having done 75 tours of the Bahrain circuit this morning.

But Russell is closing in with 68 laps this afternoon, while Piastri is just another two behind.

A common sight in F1 testing is the fluorescent paint on cars, which often confuses new fans. This is done to physically map the aerodynamic airflow, giving teams data for their analysis later. 

Isack Hadjar, Red Bull Racing

Photo by: Andy Hone/ LAT Images via Getty Images

And he is back out. The world champion is on 26 laps, which is far from this afternoon's highest total of 60 by Bortoleto. 

Going back to Hamilton, it looks as though he's getting ready to return to the track...

With 45 minutes remaining, there's still nobody threatening that fastest lap from Piastri as drivers are more in their longruns now. 

This includes Bottas and Hadjar, who are largely playing catch-up at this stage as various issues have limited running for both.

He might not be on track, but Hamilton is still much more upbeat at the moment than he was during a very disappointing 2025 at Ferrari.

"I spent a lot of time rebuilding over this winter, refocusing, really getting my body and my mind to a much better place," he said.

"Honestly, I generally feel in the best place that I've been in a long, long time with rearranging things within my team.

"And then with the car, I think we started off quite well so far. So, and it's just, it's an exciting time with this new generation of car as well, because it's all brand new. We're all trying to figure it out on the go.

"And last year we were locked into a car that ultimately I inherited. This is a car that I've been able to be a part of developing on the simulator for the last, you know, 10 months, eight months. And so like a bit of my DNA is within it.

"So I'm more connected to this one for sure."

Lewis Hamilton, Ferrari

Photo by: Sam Bagnall / Sutton Images via Getty Images

It's all quiet down at Ferrari. The mechanics are understood to have been working on the rear of the SF-26 for the past hour or so. 

'Demi' asking about prototype tyres. Basically, it depends on what Pirelli is testing so it could be closer to a soft on one occasion, but then a hard on another. 

To say it's testing, we've not been shy on wheel-to-wheel battles today. Sainz-Piastri were the latest to engage in one with the McLaren overtaking the Williams down the pit straight. 

Woops! Colapinto went deep at Turn 1 after a big lock-up with Sainz right behind him. 

Franco Colapinto, Alpine

Photo by: Mark Sutton / Formula 1 via Getty Images

Let's have another look at lap counts for this afternoon

Piastri - 39

Russell - 45

Hamilton - 24

Hadjar - 23

Sainz - 30

Colapinto - 31

Lawson - 39

Bortoleto - 39

Bearman - 25

Stroll - 7

Bottas - 16

As ever, please do continue to submit your questions as we approach the final 90 minutes of this session...anything you want from the world of F1! 

It's not been a great day so far for Cadillac. It only completed 24 laps this morning with Perez as various sensor issues limited his running. 

This afternoon, Bottas has only done 11 tours and wasn't seen on track until the second half of the session. We're still trying to find out why Bottas' running has been so limited. 

Sergio Perez, Cadillac Racing

Photo by: Kym Illman / Getty Images

Back to the track and it's still not massively busy with only Piastri, Russell, Sainz and Bortoleto in their cars. Doesn't look like any are threatening Piastri's benchmark for now. 

May I refer you to yesterday's article, where Alpine managing director Steve Nielsen, whose team is a Mercedes customer, revealed his worries for what kind of precedent this backlash sets. 

“If we're saying that a very clear set of regulations, written set of regulations can be challenged in this way, then what else is off limits?

“Everything's up for discussion then. If a certain set of teams don't like something that's very clearly written, if suddenly you can have a lobby group and change it, then you're in a whole different world.

“People invest an awful lot of time and money, and particularly money into this, in good faith, and if suddenly we're going into a world where everything can be challenged, even though it's clearly written for any reasons other than safety reasons, then I think that's a whole new world, which we've not been in before.

“So I think the compression ratio discussion is one thing, but I think it's very clear. You could say I'm biased because we've got a Mercedes engine in our car, but that's honestly what I believe.

“But I think the more fundamental question is, do we really want a sport where clearly written stuff can just be challenged because people fancy doing it? I think that's for the FIA to answer…”

Steve Nielsen, Managing Director at Alpine F1

Photo by: Mark Sutton / Formula 1 via Getty Images

So what are your thoughts on that? Harsh on Mercedes or should zero loopholes be allowed in the regulations?

It comes after the compression ratio was reduced from 18:1 to 16:1, but according to Article C.5.4.3, a static test at ambient temperature is the only method of measuring the ratio.

So Mercedes had found a way to increase its compression ratio while the engine is running, before having it at 16:1 once at ambient temp. 

On track, it's a rather quiet session at the moment with only Hamilton and Bortoleto currently running. Hamilton is using prototype tyres with mediums for the Audi.

As we all know by now, Verstappen caused a huge stir last week when he labelled the new F1 regs as "anti-racing" and like "Formula E on steroids". He then doubled down on those comments in today's press conference, before his boss Laurent Mekies was asked about the matter during the team principal session.

Stroll's car has now returned to his garage, so Aston Martin can get to work on discovering yet another problem with its AMR26...

Lance Stroll, Aston Martin Racing

Photo by: Zak Mauger / LAT Images via Getty Images

Our man Jake Boxall-Legge even offered a vague prediction of the 2026 pecking order at the end of last week's testing. 

Sainz has just set his best laptime with a 1m35.378s, which is good enough for seventh. The problem? Not only is it 1.639s off leader Leclerc, but it's close to a second behind Russell in sixth.

The gap between the front runners and midfield looks to have increased this year, Esteban Ocon previously claiming they're "seconds away".