MONTE CARLO - 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.