It is a busy track now as Charles Leclerc briefly goes fastest, before Max Verstappen clocks a 1:46.635 - 2.4 seconds quicker than Leclerc.

Max Verstappen reports having some "pulling to the right" down the straight. Possibly a similar issue to what Isack Hadjar has been experiencing with the brakes?

Max Verstappen is the early leader on the timing board with a 1:49.202 set on hard tyres. Lando Norris, on mediums, is second - half a second down on Verstappen.

Isack Hadjar on team radio: "Crazy pulling on the brakes. I nearly shunted into the wall!"

A few of the drivers are giving feedback on some early issues. Isack Hadjar says the brakes are pulling like crazy, while Oscar Piastri reports experiencing vibrations.

There's plenty of dust on the track as the drivers come out onto the track, Red Bull's Max Verstappen among the first lot to head out.

Off we go with one hour of first practice.

Marc Priestley
Former F1 mechanic on Sports Extra in Baku

I love Baku as it is unpredictable.

As a race track it is very different to anywhere else we go. It provides a whole host of different challenges.

I think there will be an awful lot to learn in this practice session.

Rosanna Tennant
5 Live F1 reporter in Baku

The drivers are just getting ready for this first hour of practice. It is going to be a hot one, I can tell you that!

You can listen to first practice coverage now on BBC Radio 5 Sports Extra and via BBC Sounds and smart speakers.

Image source, Getty Images

A couple of teams to watch particularly closely today are McLaren and Red Bull, who have brought some big upgrades to Azerbaijan.

McLaren are set to have a new floor and aerodynamic parts, as well as the return of the rotating H-Wing. They have a total of eight upgrades.

Red Bull, meanwhile, are set to have modifications to the floor body and diffuser, sidepod and mirrors on their upgraded RB22.

Andrew Benson
BBC F1 correspondent

Speaking of Hadjar, he is to stay at Red Bull as Max Verstappen's team-mate for the 2027 season.

The 21-year-old was promoted to the senior team this season after a rookie year with Racing Bulls and has managed to be closer to Verstappen on pace than any team-mate since Daniel Ricciardo in 2018.

His best result this season came with a third place at the Monaco Grand Prix.

Red Bull team principal Laurent Mekies described the move as "an easy decision".

Mekies said: "Since joining us at the start of the year, Isack has been superb on and off track, especially considering this is only his second F1 season."

Hadjar returns to Red Bull for this weekend's Azerbaijan Grand Prix after missing the past three races with a broken wrist, an injury sustained while boxing as part of his training programme.

Image source, Getty Images

Red Bull driver Isack Hadjar makes his return at this week's Azerbaijan Grand Prix after missing the past three races with a wrist injury.

The 21-year-old Frenchman was replaced by New Zealand's Liam Lawson for races in the Netherlands, Monza and Madrid after injuring his wrist while boxing.

In statement, Red Bull said Hadjar has made a "full recovery" and will replace Lawson for the Grand Prix in Baku, which runs from 24-26 September.

"The team would like to sincerely thank Liam for his professionalism, dedication and hard work over the past three races," Red Bull added.

"Stepping in under challenging circumstances, he delivered some impressive performances and made a valuable contribution to the team."

Lawson, 24, finished seventh in Zandvoort and sixth in Madrid but failed to score a point at Monza after coming 14th.

Have a listen to our Chequered Flag preview where Rosanna Tennant is joined by Harry Benjamin and Marc Priestley to look ahead to a race that is expected to suit Mercedes.

They discuss the relationship between the young Italian and his race engineer, Pete Bonnington, and hear from Kimi about how that partnership is developing.

Andrew Benson
BBC F1 correspondent

Image source, Getty Images

Kimi Antonelli says he knew from the first moment he drove this year's Mercedes that he would be transformed as a Formula 1 driver in 2026.

The 20-year-old Italian, who is running away with the world championship in only his second season in F1, is reflecting on his breakthrough year in the sport in an exclusive interview with BBC Sport.

A difficult debut season last year had left external expectations of Antonelli low at the start of 2026. But on a typically damp and cold January day at Silverstone, he already sensed that something special might be on the cards.

"It was just a few laps in the wet," Antonelli says, "but I just felt better in the car, much better than I felt last year. Also the car felt well, but I just felt better mentally in the car. Less tense, more relaxed and more mature."

Last year, he says, was "not great". "I was driving very tense most of the time, I wasn't able to extract the potential out of me," he says.

"This year, it's a lot different. The mindset has been the biggest change."

Read more of the interview here.

Here's how the top of the drivers' championship looks heading into this race. Kimi Antonelli leads George Russell by 81 points - a big gap for the others to try and bring down.

First practice: 09:30-10:30 (BBC Radio 5 Sports Extra and via BBC Sounds and smart speakers)

Second practice: 13:00-14:00 (BBC Sports Extra 2 and via BBC Sounds and smart speakers)

Image source, Getty Images

It is a glorious day in Baku with barely a cloud in the sky.

It is also pretty humid, so how will the schedule change and weather impact the drivers today?

Feeling a bit strange that we've got practice today and that the race itself is on Saturday, not Sunday?

This year, the race weekend clashes with the Azerbaijan Remembrance Day on 27 September, a national day of mourning dedicated to the military personnel who died during the Second Nagorno-Karabakh war in 2020.

As result the entire race schedule has been shifted forward 24 hours, so tomorrow will be qualifying day for the race on Saturday.

Image source, Getty Images

Hello and welcome along to our coverage of Azerbaijan Grand Prix practice!

Don't worry, you've not suddenly lost a day and it is Friday - the sessions are indeed taking place on a Thursday.

Let's crack on!