Red Bull's Daniil Kvyat emerged as the fastest driver in the second practice session of the Singapore Grand Prix, while reigning world champion Lewis Hamilton finished fourth.
Kvyat, who finished 18th in the first practice session, recovered from fuel system issues to top the standings with a time of 1:46.142, Sport24 reported.
Kimi Raikkonen of Ferrari finished second ahead of Daniel Ricciardo.
Both Mercedes drivers Hamilton and Nico Rosberg had a poor race, with the German slipping from first in the initial practice to seventh in the next one.
Meanwhile, four-time world champion Sebastian Vettel was fifth.
Hamilton holds a 53-point lead over his nearest challenger Rosberg in the drivers' championship standing after winning the Italian Grand Prix.