How McLaren addressed its Bahrain F1 2025 testing niggle in impressive style

This wasn’t how it was supposed to be as night fell on the back straight of the Bahrain International Circuit.

Just past the halfway point of 2025 Formula 1 pre-season testing, there were bigger questions facing McLaren, while Ferrari sat atop the times.

By the time Autosport reached the viewing spot behind the long Turn 11 sweep at the end of this track’s second sector, the situation was reversed. And Williams driver Carlos Sainz had forged ahead time-wise on a day and test-leading 1m29.348s.

The main question we’d put to McLaren’s Lando Norris in the day’s lunchbreak was: did the glaring impression from our trackside observations stack up? Was the MCL39 rotating beautifully at its front end, but sliding too much at the rear?

After all, Oscar Piastri had been very inconsistent in his lines through the Turns 9-10 apex in the day’s first session – where Fernando Alonso had looked totally poised and smooth in the new Aston Martin. Norris agreed with the theory.

"It feels similar, which is a good start," he said of how the MCL39 is handling compared to its predecessor, which excelled in medium-to-high-speed corners of which there are little around the Bahrain layout. "That's where we wanted to start, at least.

"Nothing's been majorly addressed. Let's say it's not like that much has changed from what we've tried to do – we’ve just tried to make the car quicker all around and add more load. It's a very simple way of looking at it, honestly. We still want to try and focus on some areas more than others.

While Alonso's Aston was looking planted, Norris' McLaren was not quite so settled early on

Photo by: Zak Mauger / Motorsport Images

"Like you're saying, we've struggled a bit more with the rear than what we would have liked over yesterday and today. But it's still early days. We're not looking at absolute outright performance."

Before Norris took over from Piastri, McLaren had the MCL39 in many pieces over the lunchbreak and into the start of the second session as it worked to incorporate its planned set-up changes.

And, in relation to the rear sliding from our evening vantage point at least, the issue was now barely visible – the topic for McLaren seemingly more of a consequence of how the rough track surface just naturally overheats the rubber.

In fact, on a race simulation at the same time as Norris, it was Charles Leclerc in the Ferrari that was grappling with faint oversteer into Turn 11. Norris was able to hit the same line time and again – his orange machine sweeping through smoothly on each occasion.

Norris, meanwhile, looked in another league. He got quicker and quicker with the more durable rubber as whatever fuel load he was on came down

At the same time, Andrea Kimi Antonelli was completing a near identical run plan to Leclerc – using the C3s over 18 laps before taking the C1s for 13, then doing 19 laps on C2s. Leclerc completed 15 tours on the C3s, then 16 with the C1s, before ending with a shorter 14-lap stint on the C2s.

The averages for this pair were impressively tight. In ‘stint one’, with what is typically Pirelli’s medium tyre at race events, Antonelli edged it by 0.175 seconds with a 1m35.902s.

In ‘stint two’, Antonelli was again fractionally faster at 1m34.738s versus Leclerc’s 1m34.765s. Then, at the end, the Mercedes was still just about ahead with a 1m34.114s compared to 1m34.182s for the Ferrari.

Antonelli and Leclerc demonstrated some remarkably similar long-run pace

Photo by: Steven Tee / Motorsport Images

Antonelli’s times were, however, coming in slightly more erratically overall and he was off the road at several points late on.

This suggests higher tyre degradation on this tricky track surface. And let’s not forget the usual caveats about engine modes and fuel loads, even as Antonelli’s 53-lap total for this whole run was just four laps shorter than the race distance here.

Norris, meanwhile, looked in another league. His three stints were completed in outlier fashion compared to McLaren’s red and silver rivals – as Norris went up the compound range from 18 laps on the C3s, to 16 on the C2s and then 10 on the C1 hards.

But what really stood out for the McLaren driver were two things.

First, his ‘stint one’ average coming in a hefty 0.388s quicker than Antonelli despite the run being of the same length. And then how he got quicker and quicker with the more durable rubber as whatever fuel load he was on came down – Norris eventually ending up with a 1m33.221s C1 average. His lap times started in the mid-1m33s before being consistently a second quicker by the time his long run ended.

He did then switch to something like a performance run – where for Ferrari, Leclerc’s earlier softer C4s flier was thwarted by traffic – but slides trying to coax a time from the C3s meant he abandoned the effort and Sainz’s time was safe. Nevertheless, his purple sector on this run was eye-catching…

Lawson spent more time in the garage than he would've liked on day two with water pressure woe

Photo by: Red Bull Content Pool

At Red Bull, an engine water pressure issue for Liam Lawson combined with the lost hour to rain in the opening session meant he did not complete the team’s planned running for the day – per squad insiders.

Lawson also did just a two-stint long run and much earlier in the second session compared to the other typical F1 frontrunners. As this was when the track wasn’t as rubbered in, the times are therefore even less comparable than usual.

After a power cut and desert rain, F1’s hive mind wonders what the last curveball of this slightly strange week in Bahrain will now be…

Although, for what it’s worth, on an 18-lap C3 opening run (akin to Norris) his averages nestled in between Norris’s leading pace and the closely matched Mercedes and Ferrari pair.

Bahrain testing has just one day to go. After a power cut and desert rain, F1’s hive mind wonders what the last curveball of this slightly strange week in Bahrain will be…

Off-track challenges with a power cut and rain have distracted the teams' focus so far

Photo by: Sauber