Rosberg takes pole for Spanish Grand Prix
Nico Rosberg will start Sunday's Spanish Grand Prix on pole position after finishing fastest in qualifying.
Reigning champion Lewis Hamilton had taken four poles out of four so far this season, with title rival Rosberg trailing in his wake - but the 30-year-old had to settle for second best in Barcelona as he could not match the German's lap of one minute 24.681 seconds.
Sebastien Vettel was again the best of the rest and will start third for Ferrari as he was the only other man to get within a second of compatriot Rosberg.
Rosberg had said on Thursday that he was ready to enjoy a "complete" weekend, having played second fiddle to Hamilton for much of the year.
Championship leader Hamilton had shrugged off those suggestions by claiming he still had the measure of a rival with whom he battled so closely for the drivers' crown in 2014.
But Rosberg, who had topped the timesheet at the end of the second qualifying session, did enough to beat Hamilton by 0.267 seconds - with Vettel over half a second further back.
"Of course I needed it sooner rather than later," Rosberg said.
"It was a good day in the office, for sure. Overtaking is more difficult at this track, so starting at the front is a really big advantage here."
Hamilton admitted he was struggling in comparison to Rosberg, but was still targeting a good day on Sunday.
"I was on the back foot," he said. "I didn't have the pace today and Nico did a great job. I did my best with it and (on Sunday) there is still a lot to play for."
The top three will all have an additional set of the faster, medium Pirelli tyres after easing through first qualifying on the hard compound as the rest of the pack had to switch to ensure progression.
Valtteri Bottas of Williams took an impressive fourth place, while Spaniard Carlos Sainz enjoyed a memorable first home qualifying session to go fifth for Toro Rosso.
His team-mate Max Verstappen was sixth ahead of the second Ferrari of Kimi Raikkonen - with Felipe Massa's Williams sandwiched in between the Red Bull duo of Daniil Kvyat and Daniel Ricciardo, who were eighth and 10th respectively.
McLaren got both of their cars into the second qualifying session for the first time this season, but the afternoons of Fernando Alonso and Jenson Button ended there.
Home favourite Alonso went 13th fastest after making an error on his final flying lap, with Button a place further back.
The Lotus pair of Romain Grosjean and Pastor Maldonado got ahead of the McLaren's but could not break into the top 10 - whilst Felipe Nasr also dropped out after qualifying 16th.
It was a poor afternoon for Force India as both of their drivers dropped out in the first session.
Nico Hulkenberg was 17th with Sergio Perez on 18th - with Sauber's Marcus Ericsson ahead of them in 16th.
Will Stevens was almost a second quicker than Manor team-mate Roberto Merhi as the Manor duo once again brought up the rear of the field.