Ferrari’s Charles Leclerc set the pace ahead of McLaren’s Lando Norris in first practice at the Singapore Grand Prix.
Leclerc was 0.076 seconds quicker than the Briton, with Ferrari’s Carlos Sainz third ahead of Red Bull’s Max Verstappen.
Norris heads into the weekend 59 points behind Verstappen in the championship and needing to keep eating into the Dutchman’s lead to keep his title hopes on track.
Singapore was the only race last year where Red Bull failed to win, and the team have come into the event this year expecting a difficult weekend.
Verstappen complained of understeer during the session and ended it 0.334secs off the pace.
After the session, the world champion was ordered to report to the stewards for an alleged breach of the sporting code, following his swearing in the official news conference on Thursday.
Verstappen’s swearing came after the FIA president Mohammed Ben Sulayem had said in an interview that he wanted F1 not to broadcast swearing from drivers during on-track sessions.
Team radio transmissions are always vetted before broadcast and are transmitted on delay so swearing can be bleeped.
Several drivers, including Verstappen, pushed back against Ben Sulayem’s comments, and Lewis Hamilton accused the Emirati of “stereotypical” language that had a “racial element”.
There were no crashes during the session on the demanding Marina Bay street circuit but Norris and Aston Martin’s Fernando Alonso both rescued major moments on the exit of Turn Eight.
Both drivers slid on to the exit kerb and fought to keep control, Alonso’s incident so large that he accidentally pressed the button saying he would pit while correcting it.
RB’s Yuki Tsunoda was fifth fastest, ahead of McLaren’s Oscar Piastri.
Australian Piastri, the winner of the Azerbaijan Grand Prix last weekend, had a delayed start to the session when his car suffered a failure on its left-rear corner during pit-stop practice.
It was repaired in time for Piastri to join the track after about 15 minutes.
He had a brush with the wall during the session without major damage to the car and ended it 0.606secs off Leclerc’s pace.
RB’s Daniel Ricciardo, whose future in the team is in doubt, was seventh fastest, from the Williams of Alex Albon, Alonso and Alpine’s Esteban Ocon.
The second session starts at 21:00 local time (14:00 BST).