Max Verstappen has been warned by Helmut Marko that reliability could still scupper his chances of a successful title defence this season.
The Dutchman has found some brilliant form this season as he looks to build on his maiden Formula 1 title from last year. He has won six of nine races so far, including five of the last six as Red Bull stamped their authority on both championships.
It was Ferrari who got the faster start at the beginning of the campaign, with Charles Leclerc winning two of the first three races. Verstappen has overcome the reliability issues he suffered with his car in those races to open up a 46-point gap at the top of the drivers' standings.
