PRACTICE DEBRIEF: Are Mercedes a step ahead in Austria – or can McLaren, Red Bull and Ferrari put up a fight?

The silver cars of Mercedes looked mighty fine as they navigated the beautiful Red Bull Ring nestled in the Styrian hills during Friday practice for the Austrian Grand Prix. But are they the one to beat in Spielberg – or can Red Bull, Ferrari and McLaren, who all brought upgrades of varying degrees, get in on the action?