Sebastian Vettel finished both free practice sessions at the Marina Bay Street Circuit inside the top five, but the German admitted the second session was a more difficult affair than the first.
The Scuderia Ferrari driver was third fastest behind Red Bull Racing duo Max Verstappen and Daniel Ricciardo in the opening session, but was only fifth fastest in the second, with team-mate Kimi Raikkonen and the Mercedes of Nico Rosberg also getting ahead of Vettel.
Vettel is looking to make more progress during Saturday’s final practice session, with the four-time Singapore Grand Prix winner knowing just how important the qualifying session will be later in the day.
“Overall we had two decent sessions,” said Vettel. “In the second one I was not entirely happy, I was struggling a little bit with the car balance, and therefore not really finding the rhythm but in general it has been a good day.
“It is very difficult to pass here, obviously we’ll try to trim everything towards qualifying. Now we have a lot of stuff to look into, before tomorrow comes: there will be another session and the opportunity to do a few more laps.
“If we get everything right we have a good chance tomorrow to position the car well.”