Ferrari's Charles Leclerc, from Monaco, finished ahead of race favourite Lewis Hamilton in the final practice session for the Singapore Grand Prix. (Photo: AFP)

Charles Leclerc produced a stunning lap in the final practice session for the Singapore Grand Prix on Saturday as Ferrari announced themselves as contenders for pole position and Sunday's race at a circuit where they were expected to struggle.

Leclerc, in his rookie season for the Italian team, has won the last two races on high-power layouts and could well be celebrating a hat-trick if he can maintain the form that saw him record a 1:38.192 second lap around the Marina Bay Street Circuit with a faultless drive.

The 21-year-old Monegasque finished 0.207 seconds ahead of Mercedes' championship leader and race favourite Lewis Hamilton after the Briton endured a frustrating session in which he spun on cold tyres when leaving the pits and ran into traffic as he set about trying to reel in Leclerc.

Leclerc's team mate Sebastian Vettel, who has played second fiddle to his younger colleague for most of the season, showed improved form to cross the line 0.619 seconds off the pace, marginally ahead of Valtteri Bottas in the second Mercedes.

The final practice session was far less fruitful for Red Bull, however, who were considered the main rivals to Mercedes coming into the race, as Alex Albon and Max Verstappen could only finish fifth and sixth fastest, more than a second behind the lead Ferrari.

The first half of the hour-long session passed with little incident until Sergio Perez clattered into a wall just in front of the pit entry lane, forcing officials to delay action for 10 minutes to allow marshals time to clean up the debris.

The Mexican was unhurt and finished 14th in his Racing Point.

Qualifying is due to commence at 1300 GMT on Saturday.