Suzuka, Japan - World championship leader Nico Rosberg ended the opening day of practice for the Formula One Japanese Grand Prix in a strong position after setting the pace in both sessions on Friday.
Rosberg set his fastest time of 1m32.250s on an overcast afternoon in Suzuka in the second of Friday's two sessions, after also having topped the timesheets at the end of the morning's opening 90-minutes of running.
His Mercedes team-mate Lewis Hamilton was second in both and while the Briton was 0.214s off his title-rival's pace in the morning he closed the gap to just 0.072s in the second session.
Hamilton heads into Sunday's Japanese round desperately needing to revive his title hopes by clinching a third successive win at the Suzuka circuit.
Rosberg extended his advantage over Hamilton to 23 points in the overall standings after the reigning champion was forced to retire 16 laps from the finish while holding a comfortable lead during the last race in Malaysia.
Their Mercedes team could also wrap up its third consecutive Constructors' crown on Sunday.
Safety car deployed
Kimi Raikkonen ended third-fastest for Ferrari, 0.323s off Rosberg's pace. The Finn had been fourth-quickest in the morning behind team-mate Sebastian Vettel, who was fifth fastest in the second session.
Vettel heads into the weekend carrying a three-place grid penalty for tipping Rosberg into a spin in Malaysia.
Max Verstappen, sixth in the morning, split the two scarlet cars in fourth.
His team-mate Daniel Ricciardo, who inherited the win in Malaysia after Hamilton retired, fell to 12th in the second session from fifth earlier after he was forced to abandon his flying lap when the virtual safety car was deployed after Esteban Gutierrez ground to a halt by the side of the track.
Force India, locked in a battle for fourth in the overall standings with Williams, continued to show a strong turn of speed.
Sergio Perez went sixth fastest ahead of German Nico Hulkenberg with the duo having set the seventh and eighth-fastest times in the morning.
Fernando Alonso, who survived an encounter with the barriers after losing control of his car at the fast Spoon corner early in the first session, ended the day eighth.
Results - Afternoon Session
1 Nico Rosberg (Germany) Mercedes - 1:32.250
2 Lewis Hamilton (Britain) Mercedes - 1:32.322
3 Kimi Raikkonen (Finland) Ferrari - 1:32.573
4 Max Verstappen (Netherlands) Red Bull - 1:33.061
5 Sebastian Vettel (Germany) Ferrari - 1:33.103
6 Sergio Perez (Mexico) Force India - 1:33.570
7 Nico Huelkenberg (Germany) Force India - 1:33.873
8 Fernando Alonso (Spain) McLaren - 1:33.985
9 Valtteri Bottas (Finland) Williams - 1:34.028
10 Carlos Sainz Jr (Spain) Toro Rosso - 1:34.086
11 Felipe Massa (Brazil) Williams - 1:34.127
12 Daniel Ricciardo (Australia) Red Bull - 1:34.150
13 Romain Grosjean (France) Haas - 1:34.241
14 Daniil Kvyat (Russia) Toro Rosso - 1:34.305
15 Kevin Magnussen (Denmark) Renault - 1:34.339
16 Jenson Button (Britain) McLaren - 1:34.398
17 Esteban Gutierrez (Mexico) Haas - 1:34.643
18 Jolyon Palmer (Britain) Renault - 1:34.760
19 Felipe Nasr (Brazil) Sauber - 1:34.824
20 Pascal Wehrlein (Germany) Manor - 1:35.292
21 Esteban Ocon (France) Manor - 1:35.400
22 Marcus Ericsson (Sweden) Sauber - 1:36.318
Results - Morning Session
1 Nico Rosberg (Germany) Mercedes - 1:32.431
2 Lewis Hamilton (Britain) Mercedes - 1:32.646
3 Sebastian Vettel (Germany) Ferrari - 1:33.525
4 Kimi Raikkonen (Finland) Ferrari - 1:33.817
5 Daniel Ricciardo (Australia) Red Bull - 1:34.112
6 Max Verstappen (Netherlands) Red Bull - 1:34.379
7 Nico Huelkenberg (Germany) Force India - 1:34.530
8 Sergio Perez (Mexico) Force India - 1:34.767
9 Fernando Alonso (Spain) McLaren - 1:35.003
10 Valtteri Bottas (Finland) Williams - 1:35.381
11 Daniil Kvyat (Russia) Toro Rosso - 1:35.446
12 Carlos Sainz Jr (Spain) Toro Rosso - 1:35.672
13 Jenson Button (Britain) McLaren - 1:35.677
14 Romain Grosjean (France) Haas - 1:35.688
15 Felipe Nasr (Brazil) Sauber - 1:35.967
16 Felipe Massa (Brazil) Williams - 1:36.169
17 Esteban Gutierrez (Mexico) Haas - 1:36.219
18 Marcus Ericsson (Sweden) Sauber - 1:36.294
19 Kevin Magnussen (Denmark) Renault - 1:36.822
20 Esteban Ocon (France) Manor - 1:37.797
21 Pascal Wehrlein (Germany) Manor - 1:37.966