Max Verstappen pipped team-mate Daniel Ricciardo as Red Bull completed a one-two in practice for the Belgian Grand Prix.
The Dutchman emerged fastest of the super-soft runners as Mercedes focussed its attention on the soft and medium tyre compounds in the second 90 minute practice session at Spa-Francorchamps.
Red Bull took advantage of the situation as Verstappen posted a 1:48.08s to top the times from Ricciardo, who was 0.25s shy on the super-soft rubber.
While Verstappen’s pace was impressive, his session ended on a negative after suffering a sudden loss of power.
Mercedes’ strategic decision saw Nico Rosberg end Practice 2 in sixth, while reigning world champion Lewis Hamilton was 13th, having spent the majority of the hit out on mediums.
However, a strong showing in the morning’s opening run saw Rosberg edge Hamilton, ensuring they ended the day third and sixth fastest overall.
Rosberg completed two runs with the Halo device fitted to his car in the first session.
Meanwhile, Mercedes elected to fit another new power unit to Hamilton’s car prior to Practice 2, which will see the Brit face a 30-place grid penalty and start Sunday’s race from the rear of the grid.
Hamilton had already been issued with a 15-place penalty prior to Practice 1 after Mercedes installed a fresh power unit and a sixth MGU-H and turbocharger.
Force India produced the surprise of practice with Nico Hulkenberg ending the day fourth quickest overall, while team-mate Sergio Perez was seventh.
Ferrari’s Sebastian Vettel was almost a second shy of the outright pace in fifth, with his opposite number Kimi Raikkonen eighth fastest.
Romain Grosjean (Haas F1) and Jenson Button (McLaren) rounded out the top 10.
A disruptive day for Fernando Alonso saw the double world champion post a time only good enough for 13th.
The Spaniard failed to clock a time in opening practice after suffering a water leak in his engine.
McLaren changed the power unit before the start of second practice which will see Alonso incur a 35-place grid penalty.
Williams also struggled for car speed with Valtteri Bottas and Felipe Massa 16th and 17th at the end of the second hit out.
Frenchman Esteban Ocon was 21st fastest on his debut for the Manor squad.
Qualifying will take place on Saturday at 2200 AEST.
Result: Formula 1 Belgian Grand Prix Practice 2
|1||Max Verstappen||Red Bull/Renault||1:48.08s||–||27|
|2||Daniel Ricciardo||Red Bull/Renault||1:48.34||+0.25||27|
|3||Nico Hulkenberg||Force India/Mercedes||1:48.65||+0.57||30|
|5||Sergio Perez||Force India/Mercedes||1:49.10||+1.01||27|
|14||Daniil Kvyat||Toro Rosso/Ferrari||1:49.91||+1.83||25|
|18||Carlos Sainz||Toro Rosso/Ferrari||1:50.19||+2.10||25|
Result: Formula 1 Belgian Grand Prix Practice 1
|4||Sergio Perez||Force India/Mercedes||1:49.27||+0.92||23|
|6||Daniel Ricciardo||Red Bull/Renault||1:49.78||+1.43||24|
|7||Max Verstappen||Red Bull/Renault||1:49.86||+1.51||24|
|8||Nico Hulkenberg||Force India/Mercedes||1:50.08||+1.74||21|
|14||Carlos Sainz||Toro Rosso/Ferrari||1:51.42||+3.07||17|
|17||Daniil Kvyat||Toro Rosso/Ferrari||1:52.30||+3.96||19|