Alonso tops opening day of rain-hit test at Silverstone

Fernando Alonso was fastest on a rain-hit opening day of testing at Silverstone, as the McLaren driver's morning time went unbeaten.

Having used the supersoft tyres, Alonso was over 1.5s clear of Esteban Ocon and three seconds ahead of the rest of the field at the lunch break. Rain then started to fall with five minutes to go until the afternoon session, which resulted in all of the afternoon running taking place on the intermediate or wet tyre and resulting in no improvement in times.

For Alonso, his lap was nearly half a second quicker than his best lap from qualifying on Saturday, which was a 1:31.740 set in Q2. The Spaniard also carried out plenty of running on the full wet tyre despite difficult conditions in the afternoon, breaking the 100-lap barrier for the day.

Ocon was driving the W07 for the first time and enjoyed a very productive morning, completing 80 laps. The Frenchman was also relatively busy un the wet as he took his tally up to 123 laps in total - the most mileage of any driver - in the afternoon session.

Third fastest was Alex Lynn in the Williams, but the Briton was 1.6s slower than Ocon and more than three seconds adrift of the fastest time. Lynn - who had a difficult weekend in GP2 at Silverstone - posted a best time of 1:34.433 as he completed all of his morning running on the medium tyre, but spent little time on track in the afternoon.

A driver to spend even less time on track was Charles Leclerc in the Ferrari. The GP3 championship leader completed just 17 laps in the morning session - posting the fourth fastest time - but then managed just one lap on full wets shortly after lunch before failing to emerge again.

Force India was one of the teams to use the softs during the morning session, with 17-year-old Russian Nikita Mazepin making his F1 debut. Mazepin enjoyed a solid first session, with his best time leaving him fifth on the timing, just 0.088s off Lynn's lap. However, Mazepin didn't run in the wet conditions.

Carlos Sainz was one of only four race drivers taking part on Tuesday - alongside Alonso, Rio Haryanto and Pascal Wehrlein in the 2014 Mercedes - and was sixth quickest in the Toro Rosso. Sainz focused on medium tyre runs as he completed 77 laps in the morning, with Toro Rosso aware of the incoming rain. The afternoon saw Sainz add a further 14 laps to his tally on full wet tyres before ending running early.

Another debutant on Tuesday was Santino Ferrucci in the Haas, with the American getting his first taste of F1 machinery. Ferrucci's best time of 1:34.866 came early in the morning on the medium tyres, but he did manage some wet running after lunch. The 18-year-old will remain in the car on Wednesday, when there forecast is also mixed

Pirelli is testing 2017 tyre compounds - but not sizes - on a 2014 car, with Wehrlein driving the Mercedes W05 during both days of testing. The Pirelli test is blind, meaning Wehrlein and the team are unaware of which prototype tyres they are running, but he was half a second adrift of third-placed Lynn at the end of the morning session. The German then didn't run in the afternoon as Pirelli only has slick tyre compounds and structure concepts to test.

Red Bull endured a frustrating morning after testing the Halo cockpit protection device during its installation lap. Pierre Gasly brought his lap tally up to seven during the first hour but then failed to emerge again in the session before the lunch break. Gasly completed plenty of laps in the wet - on both full wets and intermediates - but his best time ended up being over 12 seconds off the pace.

There was a strange moment in the afternoon when the session was red flagged due to debris on the track. In the wet and slightly windy conditions a large piece of wood fell from the start light gantry on the pit straight and was left lying next to the pit wall, with running halted while it was removed.

TIMES AND AS IT HAPPENED: Silverstone in-season test - Day 1

Silbermann says ... Radio Ga Ga

2016 British Grand Prix - Driver ratings

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