Lewis Hamilton continued his Free Practice 1 pace by topping a tricky afternoon session in Barcelona, just shy of a tenth faster than Mercedes teammate Valtteri Bottas, with the Ferrari pairing of Kimi Raikkonen and Sebastian Vettel rounding out the top four.
Red Bull's much improved package couldn't help them break the duopoly at the top, with Max Verstappen and Daniel Ricciardo trailing in fifth and sixth respectively.
A blustery day
Despite temperatures reaching the mid-twenties, a slight wind was the main cause for concern with drivers scrabbling for grip on the medium tyres, the mid-range tyre brought for the Spanish weekend by Pirelli.
Hamilton and Verstappen displayed their reactions and car control early on at Turns 13 and 9 respectively, with the latter thrown onto the gravel island by a cross-wind turning understeer into oversteer. No damage done, he returned to the pits.
Bottas was the man to beat early on, with Mercedes teammate Hamilton down in fifth. His closest rival came in the form of Raikkonen - a two time winner here - who was under a tenth away from his fellow Finn. The sister Ferrari of Vettel followed in third, with Verstappen used as a breakwater to separate the two championship leaders.
Vettel wasn't to stay behind for long, becoming the first man to venture out onto the soft tyres, and immediately beating Bottas' time by two-tenths shy of two seconds. Moments later, Raikkonen bettered the German's time on the same compound, as the prancing horses started to gallop, with times edging towards low 1:20 barrier.
Renault make improvements
But, similarly to the morning session, the Mercedes pair were not to be stifled - Hamilton lead Bottas by a tenth at the top, the two Ferraris now trailing. Nico Hulkenberg and Jolyon Palmer also showed promising pace, the former dragging his Renault to inside a second of Hamilton's first soft tyre run. With Palmer not too far behind, the French marque seem to have made big improvements.
A few garages away, a former Renault driver wasn't having a happy homecoming. The morning's oil leak and resulting engine component changes meant that Fernando Alonso failed to set a time in the first half of the session. He'd spent more time on the tennis court then the tarmac. When he did saunter out, on the medium and then soft tyres, he remained rock bottom to cap off a dreadful Friday.
Ferrari's session wasn't all promising, despite having drastically lowered the gap to Mercedes from the morning - Raikkonen was warned about his engine overheating with around half-an-hour of the afternoon left.
Red flag and race simulations
Some stray debris from the bargeboard of Carlos Sainz' Toro Rosso at the exit of Turn 9 brought out a very brief red flag.
With race simulations proving to be the order of the last 20 minutes, Hamilton's time was unrivalled, with Mercedes taking the top two positions on the timing screens for the second time today; the only drama being a late spot of rallycross for Bottas at the chicane of Turn 7.
|5||Max VERSTAPPEN||Red Bull||1:21.438||+0.636||29|
|6||Daniel RICCIARDO||Red Bull||1:21.585||+0.783||35|
|10||Carlos SAINZ||Toro Rosso||1:22.265||+1.463||34|
|12||Esteban OCON||Force India||1:22.520||+1.718||37|
|14||Sergio PEREZ||Force India||1:22.722||+1.920||32|
|18||Daniil KVYAT||Toro Rosso||1:23.236||+2.434||27|