The opening Friday practice session for the 2013 Malaysian Grand Prix would see the Williams F1 team look at reversing their fortunes from Australia where the FW35 lacked the expected performance. For this weekend Pirelli had brought their Medium and hard tyres for what again would be a race where tyres would play a major role. There again would be two DRS zones located on the circuits two long straights. With the start of the session it would be the Torro Rosso's out first shortly followed for Williams by Valtteri Bottas and shortly after Pastor Maldonado. Everyone was on the hard tyre as the drivers completed their installation laps and would return to their pits with the exception of Valtteri who would complete two laps. Last to take to the track was Webber with ten minutes completed.

The track was empty after Hulkenberg returned to his pit as the teams worked through their checks. It was very quite with only Bianchi coming out for single untimed lap. The track temperature was increasing with thirty minutes of the session completed. Chilton would come out and set a 1m:42.513 followed by a 1m:41.513. Valtteri would get ready to return as Perez set a 1m:39.653. Pastor was also back getting ready to return to his car. More drivers would start to come out onto the track with just under fifty minutes remaining. A 1m:38.830 from Perez with Button now second. A 1m:39.609 from Button remaining second. Grosjean would move into second, 1m:39.302 but Hamilton would go fastest with a 1m:38.113 seeing Grosjean now third.

For Williams both Valtteri and Pastor were back out on the track as more drivers set times. Vergne was now third followed by Grosjean and Ricciardo. Grosjean would improve to be fastest with a 1m:37.915. Now we had Webber fastest with a 1m:37.075 followed by Vettel, 1m:37.354, and Rosberg. For Williams Pastor was seventh with a 1m:38.673 while Valtteri was ninth with a 1m:39.208. Webber would find time setting a 1m:36.935. Both Red Bull's would pit along with both Williams cars. Pastor had dropped to ninth while Valtteri was down in fourteenth with neither driver improving their lap times. Rosberg was still third followed by Alonso, Sutil, Massa, Di Resta, Hamilton, Grosjean, and Pastor now in tenth. Raikkonen now moved into second with a 1m:37.003, 0.068 off Weber's time.

Twenty five minutes remaining Button would improve to be eleventh with a 1m:38.173 as Pastor and Valtteri returned to the track. Pastor was currently twelfth and Valtteri sixteenth. Both Williams drivers continued to put in laps as they worked through their programme. But Pastor would again pit with fifteen minutes remaining. Valtteri would also come in as the last ten minutes commenced. Pastor had completed twelve laps and Valtteri thirteen. The track was again busy with drivers making their last runs but there was little in the way in improvements in times. For Williams they were confident that they had gathered lots of data which they will use in the second Friday practice. Valtteri would return to the track for one last run while Pastor remained in his pit. With heavier fuel loads drivers were setting times in the 1m:42s dropping off to a 1m:45s. But Raikkonen's pace was looking good as he set a 1m:39.570 on tyres that were thirteen laps old.

Pastor was now back out with minutes remaining but with no real chance of improving his time given that his tyres were well past their best. The session would come to an end with neither Williams drivers changing their position in the times with Pastor twelfth and Valtteri sixteenth. Fastest was Webber from Raikkonen, Vettel, Alonso, Rosberg, Sutil, Massa, Di Resta, Hamilton, and Grosjean tenth. Both Williams drivers were still well of the pace but the real test will be how they perform in FP2 after having worked through the data collected this morning.

Pos  Driver         	  Team		        Time     Laps
 1.  Mark Webber          Red Bull-Renault      1m36.935s 15
 2.  Kimi Raikkonen       Lotus-Renault         1m37.003s 15
 3.  Sebastian Vettel     Red Bull-Renault      1m37.104s 21
 4.  Fernando Alonso      Ferrari               1m37.319s 13
 5.  Nico Rosberg         Mercedes              1m37.588s 19
 6.  Adrian Sutil         Force India-Mercedes  1m37.769s 17
 7.  Felipe Massa         Ferrari               1m37.771s 15
 8.  Paul di Resta        Force India-Mercedes  1m37.773s 15
 9.  Lewis Hamilton       Mercedes              1m37.840s 18
10.  Romain Grosjean      Lotus-Renault         1m37.915s 17
11.  Jenson Button        McLaren-Mercedes      1m38.173s 16
12.  Pastor Maldonado     Williams-Renault      1m38.673s 16
13.  Sergio Perez         McLaren-Mercedes      1m38.830s 17
14.  Nico Hulkenberg      Sauber-Ferrari        1m39.054s 17
15.  Esteban Gutierrez    Sauber-Ferrari        1m39.204s 16
16.  Valtteri Bottas      Williams-Renault      1m39.208s 19
17.  Jean-Eric Vergne     Toro Rosso-Ferrari    1m39.284s 17
18.  Daniel Ricciardo     Toro Rosso-Ferrari    1m39.567s 16
19.  Giedo van der Garde  Caterham-Renault      1m40.728s 17
20.  Jules Bianchi        Marussia-Cosworth     1m40.996s 14
21.  Charles Pic          Caterham-Renault      1m41.163s 18
22.  Max Chilton          Marussia-Cosworth     1m41.513s 14