Mercedes set an all-time record of four consecutive one-twos at the start of a season as Valtteri Bottas beat Lewis Hamilton to win the Azerbaijan Grand Prix.For the fourth race in a row, Ferrari were unable to challenge Mercedes - and again there were questions about the strategy chosen by the Italian team.Sebastian Vettel finished third, never very far behind the Mercedes, but team-mate Charles Leclerc finished fifth when it looked for a while as if he might have been able to take fourth ahead of Red Bull's Max Verstappen.Leclerc's consolation on a weekend that he had looked like dominating until crashing in qualifying was a point for fastest lap.The result makes Mercedes the first team ever to start the season in such a dominant fashion and puts their drivers in an enviable position in the championship.Bottas returns to the lead of the championship, leading Hamilton by the point he gained for fastest lap in Australia. Vettel is 35 points behind.