The 27-year-old - whose sole win in Formula One came in last year's China Grand Prix - timed 1min 32.330sec to give Mercedes their second successive pole position.
Manama: German Nico Rosberg saluted his Mercedes team for their overnight work on improving his car enough to land him pole position on Saturday for Sunday's Bahrain Grand Prix.
Story first published on: Saturday, 20 April 2013 17:48
The 27-year-old - whose sole win came in last year's China Grand Prix - secured the Mercedes team's second successive pole when he clocked a best time of one minute and 32.330 seconds in the final Q3 segment of the qualifying hour.
This enabled him to outpace Germany's three-time defending world champion and championship leader Sebastian Vettel of Red Bull by two-tenths of a second. Spain's two-time world champion Fernando Alonso of Ferrari was third fastest.
"Am I surprised? A little bit," Rosberg admitted. "It wasn't really clear who was the quickest car over one lap.
"I was a bit happier than yesterday (Friday). We worked overnight to improve the car so I'm really, really happy.
"It's a fantastic result. It's great for tomorrow (Sunday). Of course tomorrow will be a tough race with rear degradation especially, but we are in a good position for me.
"I really want to kick-start my season. It has been a rough ride in the first three races. Today was my first real qualifying. I'm OK for the race tomorrow.
"For sure the competition will be tough definitely. It's difficult to say if we have enough pace to win the race tomorrow but for sure we'll try hard to win."
Rosberg has finished only one race of three this season while his Mercedes team-mate Briton Lewis Hamilton has enjoyed two successive podiums.
But Hamilton's luck ran out on Saturday when his car failed in the morning's final free practice session and the subsequent repairs required a new gearbox which, in turn, handed him a mandatory five-place grid penalty.
He qualified fourth, behind Alonso, but will start the race ninth. Brazilian Felipe Massa will start from fourth place in the second Ferrari after qualifying sixth behind Australian Mark Webber who was given a three-place grid penalty brought forward from last weekend's Chinese Grand Prix.
Vettel was pragmatic about his performance and his hopes of repeating his victory in last year's race at the dusty and sand-strewn Bahrain International Circuit.
"Congratulations to Nico, it was all his today," he said. "When I crossed the line I saw I didn't go first. I didn't know how much was missing.
"The lap was fine, but it was clear even with a perfect lap that Nico was unbeatable today. We managed to save tyres for the race and, for sure, it is good to start on the front."
Alonso, victorious in a strategic race focused on tyre-preservation last weekend in China, said: "We tried to complete the second flying lap and it was similar until the last corner...
"Then, at that exit, I saw I was one-tenth slower so we decided to come in and save one lap on those tyres.
"You never know if you have to use them again. Normally, in qualifying, we struggle a lot and the car is very competitive in the race.
"This time, we start with the leaders and I think that we can fight for the podium."
Briton Paul di Resta qualified in seventh place, but thanks to the two penalized drivers will start the race from fifth ahead of his Force India team-mate German Adrian Sutil.
Finn Kimi Raikkonen of Lotus also profited from their misfortunes to transform ninth into seventh while Briton Jenson Button of McLaren, who qualified 10th, will start from that position.
Starting grid for Sunday's Bahrain Grand Prix following final qualifying on Saturday:
Nico Rosberg (Mercedes)
Sebastian Vettel (Red Bull)
Fernando Alonso (Ferrari)
Felipe Massa (Ferrari)
Paul di Resta (Force India)
Adrian Sutil (Force India)
Mark Webber (Red Bull)
Kimi Raikkonen (Lotus)
Lewis Hamilton (Mercedes)
Jenson Button (McLaren)
Romain Grosjean (Lotus)
Sergio Perez (McLaren)
Daniel Ricciardo (Toro Rosso)
Nico Hulkenberg (Sauber)
Valtteri Bottas (Williams)
Jean-Eric Vergne (Toro Rosso)
Pastor Maldonado (Williams)
Charles Pic (Caterham)
Jules Bianchi (Marussia)
Giedo van der Garde (Caterham)
Max Chilton (Marussia)
Esteban Gutierrez (Sauber)