Test drivers outperform struggling McLaren in Barcelona

McLaren and Ferrari's attempts to play catch-up at either end of the grid caught early setbacks in free practice one for the Spanish Grand Prix.

Sporting a new livery and several upgrades, McLaren had hoped to see improvements in Barcelona, however they again encountered problems with Jenson Button complaining of balance issues and Fernando Alonso's engine smoking heavily before taking to the track.

To make matters worse for the former world champions, they had to sit and watch test drivers Rafaelle Marciello (Sauber), Jolyon Palmer (Lotus) and Susie Wolff (Williams) all clock faster times over the 90-minute session.

At the front, it was business as usual for Mercedes as Nico Rosberg pipped Lewis Hamilton to top spot, the German's time of one minute 26.828 seconds beating his team-mate by 0.070secs.

Ferrari again ran them closest of anyone else, but they remain a second behind despite bringing a host of new parts for the start of the European season, Mercedes' own development in the three-week break from Bahrain keeping Sebastian Vettel and Kimi Raikkonen almost a second behind.

Toro Rosso continue to show signs of strength, following the Italian constructor in fifth and sixth. Carlos Sainz and Max Verstappen enjoyed a productive start to the weekend, the Spaniard clocking 1:28.132 at his home grand prix.

A new, shorter nose cone for Daniil Kvyat failed to have the desired effect on his Red Bull as he finished seventh, while Daniel Riccardo managed to haul himself into ninth after problems with the back end of his car early in the day.