(CNN) -- Mercedes are preparing for a "true test" in Sunday's Monaco Grand Prix after Nico Rosberg catapulted the Silver Arrows to the fastest time in practice, with teammate Lewis Hamilton a close second. The German driver, who was raised in Monte Carlo, set the pace around the city's tight and twisting streets with a leading lap of one minute 14.769 seconds on Thursday. "It was a very productive day for us," said Rosberg, who has taken pole position for Mercedes at the last two races in Bahrain and Spain but failed to translate that into podium finishes due to the team's struggles with tire degradation.
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Nico Rosberg sets the quickest time for Mercedes in practice for Monaco Grand Prix
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Mercedes boss Ross Brawn warns Sunday's race is the real test for his team
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Fernando Alonso can become first driver to win in Monaco GP for three teams
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Red Bull lament practice pace but remain confident
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