Ricciardo and Red Bull in the mix in Singapore's FP1

Daniel Ricciardo topped the opening practice session for this weekend's Singapore Grand Prix, edging his Red Bull team mate Max Verstappen by 0.201s.

Sebastian Vettel, Kimi Raikkonen and Nico Hulkenberg complete the top-five while Mercedes drivers Lewis Hamilton and Valtteri Bottas focused on race set-up work, refraining from running on Pirelli's fastest hypersoft tyre.

2018 Singapore Grand Prix - Free Practice 1

The fifteenth round of the F1 world championship kicked off under clement Singapore skies and 32 degrees Celsius air temperature. The conditions however will be very different later on when the sun sets and light are turned on around the Marina Bay circuit.

Marcus Ericsson was the first driver to venture out, his Sauber shod with Pirelli's soft tyres, the hardest compound supplied here this weekend.

As a reminder, the hypersoft rubber is also available to teams in Singapore, the pink-rimmed tyre making its first appearance since Canada.

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Mercedes' Valtteri Bottas, running on ultrasofts, put a 1m43.428s benchmark time on the board, with Sebastian Vettel clocking in 0.331s behind the Finn.

Bottas quickly improved and Lewis Hamilton slotted himself in second to make it a Mercedes 1-2.

Twenty-five minutes into the session, in the Ferrari garage, Kimi Raikkonen was informed of an issue that would keep the Finn stranded for the following 25 minutes.

Meanwhile, Hamilton put himself at the top of the timesheet, leading Bottas, the Red Bull pair of Daniel Ricciardo and Max Verstappen, and Force India's Sergio Perez, with all five cars separated by just three tenths of a second.

Winding up his speed, Ricciardo barged through the Mercedes blockade with the first sub-1m42s lap of the day, completing a lap the soft tyre in 1m41.814s.

Oddly, the Aussie radioed in to express his discontent with his lap, claiming that "driveability sucked that lap".

After forty-five minutes of action, Bottas briefly wrestled back the lead for Mercedes, before Hamilton demoted his team mate to second with a 1m41023s.

Sneaking up from behind however after a rather discrete presence in the session, Raikkonen and Vettel were suddenly charging. Stringing together a series of purple sectors Vettel's efforts produced a 1m39.997s lap with his team mate snapping a t his heals in second.

One would have noted that Vettel's lap, at that point, was almost one second faster than the very best lap set last year around Marina Bay.

The Red Bull camp, armed with the hypersoft compound, wasn't to be outdone by the prancing horses however.

Both Verstappen and Ricciardo joined Vettel under the 1m40s barrier, with the latter putting in a lap in 1m39.711s, with the Dutchman just 0.201s behind, both drivers confirming Red Bull Racing's impressive early pace.

Mercedes' drivers had yet to set a lap on Pirelli's pink rubber, with Hamilton and Bottas both preferring to continue on the soft tyre as the Silver Arrows pair worked on longer runs.

As the first free practice session reached its conclusion with no major changes at the front, Stoffel Vandoorne, still lingering at the bottom of the time sheet for McLaren, was recalled back to the pits with an apparent hydraulic loss.

There was drama in the Sauber camp however when Charles Leclerc misjudged his entry into Turn 13, tearing off the front right of his C37. It was a rare but costly mistake for the future Ferrari driver.

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