Defending triple world champion Sebastian Vettel outpaced home hero Fernando Alonso to clock the fastest time in Friday's second free practice session ahead of this weekend's Spanish Grand Prix.
The 25-year-old Red Bull driver narrowly edged out the Ferrari man with a best time of one minute 22.808 seconds after Alonso had delighted his compatriots during a wet morning session by clocking the early fastest time.
Just 0.083 seconds covered the top three men as Alonso split the two Red Bulls of Vettel and his team-mate Mark Webber, who was third fastest.
After an all-Mercedes battle involving both Nico Rosberg and Lewis Hamilton in the early stages of the afternoon session, it was Alonso and the Red Bulls that dominated the lead order through the low-fuel runs in the final part.
Finn Kimi Raikkonen of Lotus was fourth fastest ahead of Brazilian Felipe Massa in the second Ferrari, Hamilton and Rosberg, with the struggling McLarens of Jenson Button and Sergio Perez down in 12th and 13th respectively.
Hamilton spun his Mercedes at Turn 11 during the early runs, swiftly rejoining without problems and ultimately taking sixth on a day when tyre wear was again a major issue with Paul di Resta suffering a major scare when the left rear tyre on his Force India car delaminated on the main straight.
The Scot parked his car on the grass. He ended up 10th, two places behind team-mate Adrian Sutil.
Putting on a show
Home hero and two-time champion Fernando Alonso of Ferrari clocked the fastest time in Friday morning's opening free practice session for this weekend's Spanish Grand Prix.
On a damp morning with much wet weather at the Circuit de Catalunya, Alonso clocked a best lap in one minute and 25.252 seconds to outpace team-mate and nearest rival Brazilian Felipe Massa by 0.203 seconds.
The conditions made it difficult for any of the teams or drivers to acquaint themselves properly with the rafts of upgrades fitted to their cars since the four season-opening flyaway races.
It was only coming into the final quarter of an hour that slick tyres were viable, but it remained treacherous and there were enough wet and slippery patches to make it difficult for everyone.
With so many developments to try, the teams were less reticent about coming out earlier than is usual and the crowd had a decent amount of track activity to enjoy throughout the morning.
They also showed their appreciation of Alonso's efforts as he tried to deliver faster laps to thrill his fans.
Alonso spent a while as the fastest man during the wet running, though he tumbled down the order as conditions improved.
Going into the closing seconds, Massa was the latest to burst to the top of a constantly fluctuating list of fastest men as the field began to work with their slick tyres.
Alonso finished the morning with a flourish, setting his best lap as the two red Ferraris set the pace.
Frenchman Jean-Eric Vergne of Toro Rosso was the the first man to be quick on slicks and he ended up third-fastest ahead of compatriot Romain Grosjean of Lotus, German Adrian Sutil of Force India and Briton Lewis Hamilton in his leading Mercedes.