Baku - Max Verstappen crashed again while Valtteri Bottas topped the times for Mercedes in Friday morning's opening free practice session for this weekend's Azerbaijan Grand Prix.

The young Dutchman has crashed at all three Grands Prix this season and came into this weekend under pressure to regain his composure and some consistency but slid his Red Bull car into the wall after only half an hour.

The damage was extensive enough to wreck his session as Finn Bottas rose to the top of the timing screens with a best lap of one minute and 44.242 seconds around the high-speed street circuit.

Last year's race winner Australian Daniel Ricciardo, who was also victorious in China two weeks ago, was second fastest for Red Bull only 0.035 seconds behind Bottas.

Verstappen, 20, lost control of his car at Turn Three and smashed into the barriers.

He has been involved in a series of incidents this year. In Australia, he crashed and finished sixth. In Bahrain, he crashed in qualifying and collided with Hamilton in the race before retiring - and in China he slid off in a misjudged attempt to pass Hamilton before crashing into Vettel.

Mexican Sergio Perez was third quickest for Force India, eight-tenths off the pace, ahead of defending four-time champion Briton Lewis Hamilton in the second Mercedes, nine-tenths adrift.

Frenchman Esteban Ocon was fifth in the second Force India ahead of Verstappen and two-time champion Spaniard Fernando Alonso of McLaren.

World championship leader and four-time champion German Sebastian Vettel was 10th quickest for Ferrari behind Russian Sergei Sirotkin and Williams team-mate Canadian Lance Stroll.