Swapping to the medium tyres for qualifying style runs in FP2, Nico Rosberg set the pace ahead of Kimi Raikkonen.
Although it was Ferrari and Fernando Alonso who held the advantage during the hard tyre runs on Friday afternoon ahead of Mercedes and Lewis Hamilton, it was their team-mates who came to the fore on the medium tyre runs.
Swapping over after the first 30 minutes, Rosberg posted a 1:39.909 to beat Raikkonen to the P1 slot by 0.035s.
Third place went to Sebastian Vettel, who managed his best time on his second flying lap. While others dropped off after the first, the Red Bull racer found more speed to finish up with a 1:39.970.
Hamilton was fourth quickest ahead of Alonso, Felipe Massa and Daniel Ricciardo in a session that saw less than four tenths cover the top seven drivers.
Jenson Button was eighth with Valtteri Bottas and Nico Hulkenberg completing the top ten.
Meanwhile, it was a better session for Lotus in that they managed nine laps - three more than this morning - and even set a time.
While Pastor Maldonado was stuck in the pits with his E22 in pieces, Romain Grosjean managed 14 at the start of the session with a best time of 1:42.531. His first stint came to an end as he limped his way back into the pits while his second, which was five laps, ended on the side of the track.
Kamui Kobayashi didn't set a time despite his Caterham team working furiously to get his CT05 up and running.
01 Nico Rosberg Mercedes 1:39.909 30 laps
02 Kimi Raikkonen Ferrari 1:39.944 +0.035 30 laps
03 Sebastian Vettel Red Bull 1:39.970 +0.061 30 laps
04 Lewis Hamilton Mercedes 1:40.051 +0.142 32 laps
05 Fernando Alonso Ferrari 1:40.103 +0.194 29 laps
06 Felipe Massa Williams 1:40.112 +0.203 34 laps
07 Daniel Ricciardo Red Bull 1:40.276 +0.367 29 laps
08 Jenson Button McLaren 1:40.628 +0.719 28 laps
09 Valtteri Bottas Williams 1:40.638 +0.729 35 laps
10 Nico Hulkenberg Force India 1:40.691 +0.782 34 laps
11 Jean-Eric Vergne Toro Rosso 1:40.777 +0.868 33 laps
12 Kevin Magnussen McLaren 1:41.014 +1.105 20 laps
13 Adrian Sutil Sauber 1:41.257 +1.348 28 laps
14 Daniil Kvyat Toro Rosso 1:41.325 +1.416 32 laps
15 Esteban Gutierrez Sauber 1:41.407 +1.498 34 laps
16 Sergio Perez Force India 1:41.671 +1.762 25 laps
17 Romain Grosjean Lotus 1:42.531 +2.622 14 laps
18 Max Chilton Marussia 1:43.638 +3.729 20 laps
19 Jules Bianchi Marussia 1:43.752 +3.843 29 laps
20 Marcus Ericsson Caterham 1:45.703 +5.794 31 laps
21 Kamui Kobayashi Caterham
22 Pastor Maldonado Lotus
Friday's Pictures From Sepang
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