Max Verstappen emerged quickest despite ending Friday practice in the barriers after an incident-filled second session ahead of the Azerbaijan Grand Prix.

The Dutchman proved the class of the field as Red Bull showed encouraging signs around the challenging Baku City street circuit.

Several drivers made errors in the two 90 minute sessions as they struggled for grip, resulting in collisions with the barriers and trips down escape roads.

Verstappen set the pace by clocking a 1:43.362s effort on super-soft tyres which was 0.100s faster than nearest rival Valtteri Bottas (Mercedes).

However, the teenager, who topped opening practice, blotted his copybook in the final seconds of second practice when he lost control of his Red Bull, finding the barriers at Turn 1.

“It was very weird to be honest,” said Verstappen when asked about the crash.

“I locked up and tried to play it safe and stay on the exit road, but then suddenly I lost the rear and had a four wheel powerslide into the barriers.”

Red Bull’s pace was backed up by Daniel Ricciardo who ended the day third fastest, just 0.011s shy of Bottas.

“It has been a pretty good day, both of us (Red Bulls) were in the top three in both sessions,” said Ricciardo.

“This morning, even though I was second, I wasn’t that content with my session. There was still a lot of room for improvement from myself and the car.

“I believe we made improvements and there is still a little bit to find, but I’m happy with how we ended the day.”

Kimi Raikkonen was fourth fastest in front of Ferrari team-mate Sebastian Vettel, who endured several trips down escape roads as he pushed the limits in search of speed.

Vettel was only 0.253s adrift of Verstappen in what proved to be a hotly contested session.

Williams Lance Stroll surprised by posting the sixth quickest time ahead of Force India’s Sergio Perez, who clattered the barriers at Turn 8 in first practice.

Among a group of drivers to make mistakes, Toro Rosso’s Daniil Kvyat was eighth, while the top 10 was rounded out by Esteban Ocon (Force India) and Mercedes’ Lewis Hamilton, who struggled for outright pace.

Fernando Alonso’s day ended prematurely when the McLaren driver suffered a gearbox failure, leaving him 12th behind Felipe Massa.

The second session was red flagged at the halfway point when Renault’s Jolyon Palmer found the wall at Turn 8, which prompted a 10 minute stoppage to clear the track.

Meanwhile, Haas F1’s Romain Grosjean battled brake issues that left him languishing down in 20th position.

Result: Formula 1 Azerbaijan Grand Prix Practice 2

Result: Formula 1 Azerbaijan Grand Prix Practice 1