Mercedes' Valtteri Bottas crashed out of practise session one as Red Bull's Max Verstappen was the fastest. Ferrari's Sebastian Vettel was 2nd fastest (1:40.426) and last year's race winner Lewis Hamilton (1:40.925) finished behind the German.
But the highlight from the opening session was Bottas crashing into the wall at turn 19 after the Finn looked to have lost control of the car when exiting turn 18.
"Sorry guys" was Bottas' response to his team on the radio just moments after the crash.
The incident did cause a red flag with just over 20 minutes left of the session. Bottas was, however, 4th fastest in the session.
Red Bull the ones to watch this weekend?
It's so far so good for Red Bull after practice session one, thanks to Verstappen recording a 1:40.259 which proved to be the fastest lap.
Red Bull are expected to be Mercedes' main rival for this weekend in Marina Bay as the circuit suits both teams more than the power of the Ferraris.
Verstappen has led his team to two victories in 2019 with dramatic wins in Germany and Austria. His teammate Alexander Albon was 5th fastest with a 1:41.467 who has so far been very impressive since taking over Pierre Gasly's seat.
Vettel may have been second fastest but his teammate Charles Leclerc was second from last despite only going out for 12 laps.
Is the practise times shaping up a Mercedes and Red Bull at the front with Ferrari watching from behind?
Sainz and Hamilton nearly collide
In the early stages of P1, Hamilton and McLaren's Carlos Sainz Jnr very nearly collided with each other.
The Spaniard was aiming to do a flying lap and believed the Briton was in the way of his racing line.
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