Norris leads rain-disrupted opening practice in Montreal

McLaren’s Lando Norris set the fastest time in Friday’s truncated and largely irrelevant wet-to-dry first practice at the Circuit Gilles Villeneuve, the Briton preceding the Ferrari duo of Carlos Sainz and Charles Leclerc.

The session kicked off with a 20-minute delay in very wet conditions but on a shortened 40-minute timetable.

Conditions evolved enough for at least half of the runners to put some laps under their belt, although performance was nowhere to be found, much less encouraged in the treacherous session that was also halted by a red flag in the wake of an off by Sauber's Zhou Guanyu.

• Canadian Grand Prix Free Practice 1 - Results

Montreal’s weather conditions wreaked havoc on the start of Friday’s action, with several rains spells interspersed with relief periods drenching the track.

Minutes before FP1 was scheduled to start, race control issued a message that the session would start on time at 13h30 local time but the pitlane exit would remain closed as crews worked on clearing the standing water out on the track.

As the draining work continued, the safety car and the medical car began lapping the circuit to monitor conditions.

However, at 13h50 the deafening silence was finally broken by none other than Lewis Hamilton who took to the track for a few exploratory laps on the intermediate tyre.

Hamilton’s former Mercedes teammate Valtteri Bottas was a second taker of the low-grip conditions, the Finn opting for full wets. But conditions remained soaking wet despite the clearing skies and the sun shining through.

Gradually however, track evolution was underway and traffic increased, with half the field testing the waters.

But ten minutes in, Sauber’s Zhou Guanyu was caught out by the tricky conditions, the Chinese driver clattering the wall at Turn 5 and bringing proceedings – and his session – to a halt as the first red flag of the weekend was brandished.

Zhou stricken car was swiftly recovered and the action resumed with 23 minutes left on the clock. At that point, only three drivers – Bottas, Hamilton and Verstappen – had registered a time. But the running quickly ramped up and times tumbled.

There were several rotations at the top of the timing screens but Sainz and Leclerc – running on Inters like the bulk of the field – went top with over a second in hand over their closest pursuers.

With just ten minutes to go, those who were running – only eleven drivers in all - opted to pit, seemingly to wait for conditions to dry up enough for slick tyres.

This turned out to be the case, with Ferrari and Mercedes’ chargers, Verstappen and Norris venturing out on Pirelli’s soft compound dry rubber.

The McLaren driver eventually concluded the session on top, from Sainz and Leclerc but times remained very disparate and mostly irrelevant as everyone managed – even Alpine reserve Jack Doohan – to put at least 4 laps on the board.

One can only hope that teams will be able to make up in FP2 for the opening session’s lack of running, but prospects were looking bleak.

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