Barcelona Final Test Day One: Williams Unleashed as Massa tops the Charts

The Williams team's relatively anonymous path through winter preparation ended in Barcelona this afternoon as Felipe Massa ended the first day of the final pre-season test comfortably fastest by three quarters of a second.

However, it was another tough day for McLaren who were forced to abandon the day's sessions with just seven laps on the board, and for Mercedes who might well have challenged Williams for the best time had they not suffered a hybrid system failure.

Massa's best lap came in the afternoon of what was a thoroughly productive outing for the Grove squad, his 1m23.500s on soft tyres blitzing Lewis Hamilton's morning best on medium rubber.

The Brazilian had already managed a medium tyre run better than Hamilton by two tenths of a second.

Williams managed a three-figure lap count but the biggest mileage was covered by Sauber for whom Marcus Ericsson completed 122 laps including a successful race simulation.

The Swiss team then vaulted to second on the timesheets courtesy of two late supersoft tyre runs which brought Ericsson to within 0.776s of Massa's best.

Mercedes' problem-free test streak ended when Lewis Hamilton missed all of the afternoon running because of an MGU-K failure.

In the morning he had been impressively quick, emerging fastest of all by almost a second using Pirelli's medium compound tyres, while also running the most laps of all to the mid-point of the day.

Daniil Kvyat and Red Bull provided the first red flag of the day within minutes of the green light coming on but the Russian and his machine were retrieved from the end of pit lane and were soon back on their way though the team's afternoon wasn't without issues. A mechanical run stopped the team from completing a race simulation and Kvyat was restricted to short data gathering runs in the afternoon while the team awaits replacement parts overnight.

There was no showboating from Romain Grosjean and Lotus this time as they managed 75 laps, better only than Mercedes and McLaren, in a quiet first day for Enstone.

Kimi Raikkonen, too, was neither busy on track nor headline quick with the Ferrari which, nonetheless, appeared to run trouble free throughout the day.

All eyes were on local hero Carlos Sainz Junior in the Toro Rosso which has been heavily modified since its introduction to the point where the team considers it virtually an all new car.

Sainz brought out the days second red flag an hour into the afternoon when it stopped out on track but the team were able to get him back out on track before the end.

For McLaren Honda, the trials continue. The team temporarily fitted McLaren sourced parts to the MGU-K unit in an effort to solve the seal problems that blighted last week's test. However, Jenson Button managed just seven laps in the morning with a best lap more than six seconds off Lewis Hamilton's medium tyre best to that point.

Half way through the afternoon they announced that a hydraulic leak had forced an engine change which meant they were finished for the day with just their morning's meagre lap tally laps to add to the data store.

Barcelona Final Test - Day One

1 Felipe Massa Williams 1:23.500s 103 laps

2 Marcus Ericsson Sauber 1:24.276s 0.776s 122

3 Lewis Hamilton Mercedes 1:24.881s 1.381s 48

4 Daniil Kvyat Red Bull Racing 1:25.947s 2.447s 75

5 Romain Grosjean Lotus 1:26.177s 2.677s 75

6 Kimi Raikkonen Ferrari 1:26.327s 2.827s 80

7 Carlos Sainz Jr. Toro Rosso 1:26.962s 3.462s 86

8 Jenson Button McLaren 1:31.479s 7.979s 7