Monaco Grand Prix: Daniel Ricciardo on top as Red Bulls fly in second practice
To endorse Red Bull`s revival, Ricciardo`s record-breaking teenager team-mate Max Verstappen was fourth-fastest just behind Rosberg.
Monaco: A determined Daniel Ricciardo flew to the fastest time in Thursday`s action-packed second free practice for Sunday`s 74th running of the classic Monaco Grand Prix as a revived Red Bull left Mercedes gasping in pursuit.
The Australian clocked a best lap time around the Mediterranean street circuit in one minute and 14.607 seconds to finish more than six-tenths of a second faster than defending three-time champion Lewis Hamilton and nearly nine-tenths clear of championship leader Nico Rosberg.
To endorse Red Bull`s revival, Ricciardo`s team-mate record-breaking teenager Max Verstappen was fourth-fastest just behind Rosberg, the Dutchman in a car that did not have the same updated Renault engine used by the Australian.
"I always enjoy myself here," said a beaming Ricciardo. "Obviously, the engine helps a little bit, but we have got a good car round here too - so it`s a bit of both.
"I`ve got good confidence in the car so that`s the most important thing around here... Let`s see how we go in qualifying. Today, I`m happy....
"It`s certainly one where you can find a little bit more if you`re willing to push it on the limit. I`ve always enjoyed it here.
"If the track doesn`t change much before Saturday, I`m confident. Winning is definitely my aim and, basically, I feel it`s my time - and this is the best track to do that."
Russian Daniil Kvyat, the man replaced at Red Bull by the 18-year-old Dutchman, was fifth for Toro Rosso ahead of his team-mate Spaniard Carlos Sainz and seventh-placed Finn Kimi Raikkonen of Ferrari.
Mexican Sergio Perez was eighth for Force India ahead of four-time champion German Sebastian Vettel in the second Ferrari and 2009 champion Briton Jenson Button of McLaren Honda.
"That was a massively impressive session for Daniel," said Red Bull team chief Christian Horner. "On both sets of tyres, he`s been quicker than the Mercedes.
"Nobody knows, of course, what fuel levels or engine modes people are using, but it`s certainly a positive start. Both short runs and long runs looked very competitive."Vettel was one of several drivers to make close acquaintance with the barriers around the steel-lined streets of the Mediterranean principality in a session, like the opening one in the morning, which produced a series of Virtual Safety Car (VSC) interruptions.
These were prompted by unexpected off-track excursions from Brazilian Felipe Nasr of Sauber at Ste Devote, Frenchman Romain Grosjean hitting the barriers at the exit of the chicane in his Haas, followed in a similar accident by Indonesia`s Rio Haryanto of Manor.
Vettel then lost control at Mirabeau and damaged the rear of his Ferrari. "I crashed," he said on team radio. "I damaged the rear wing... Get a spare ready."
Dane Kevin Magnussen followed suit at the final corner when he went into the barriers at the exit of Rascasse just before Vettel `kissed` the wall at Ste Devote again.
Mercedes steered clear of trouble but were unable to repeat their supremacy of the morning`s opening free session when Hamilton topped the times.
As the afternoon session ended, Hamilton suffered a minor setback that revealed the pressures on his team - a jack flipping during work on his car and smashing a hole in the nose section.
Without a win in seven races since clinching his third world title at last year`s United States Grand Prix, Hamilton trails Rosberg by 43 points in this year`s championship.
The Mercedes pair collided on the opening lap of the Spanish Grand Prix earlier in May and both have stressed the need to avoid a similar accident on the cramped streets this weekend.
Hamilton looked imperious in the morning when he topped the times, making use of the latest new `ultra-soft` Pirelli tyres for he first time, but he could not match Ricciardo in the second session.