Stricken world champion Marc Marquez edged Jorge Lorenzo to finish fastest rider in Friday's free practice for this weekend's Australian MotoGP at Phillip Island.

Marquez, who broke his left hand in training last month and cannot successfully defend his world title, clocked the fastest lap of one minute 29.383 seconds to shade fellow Spaniard Lorenzo by 0.050sec.

Only Lorenzo and his Italian Movistar Yamaha team-mate Valentino Rossi can win this year's MotoGP crown heading into the final three races of the season.

World championship leader Rossi, who was third quickest behind Lorenzo in morning practice, slipped down the time charts to finish ninth quickest overall, 0.658sec down on Marquez.

Repsol Honda's Marquez, who is 86 points adrift of Rossi on the championship standings with a maximum of 75 points available, trailed Lorenzo in the morning session.

But as the sun came out and the track dried the reigning MotoGP world champion ended the day on top, still some way short of Lorenzo's track pole record of 1:27.899 set in 2014.

"Today was a good day -- I enjoyed it and we improved the set-up, which is most important," Marquez said.

"We did the correct steps and precisely, which is not easy.

"But I think tomorrow we must improve a lot because it looks like the Yamaha riders -- especially Jorge -- their rhythm is really fast, so we will keep working hard."

Lorenzo improved by over half-a-second throughout in FP2, where just under nine-tenths of a second separated the top 13 riders.

Team Suzuki Ecstar's Maverick Vinales bounced back from his failure to finish at Motegi in Japan last weekend to complete the provisional front row, just 0.135sec off the pace of Marquez.

Italian Andrea Iannone (+0.161sec) was fourth fastest on his Ducati ahead of LCR Honda's Cal Crutchlow (+0.196sec).

Last weekend's Japanese GP winner Dani Pedrosa (+0.493sec) was in sixth.

"Today we started to work on the setup of the bike, trying to think about tomorrow and Sunday's race, and we tested the asymmetrical front tyre," Pedrosa said.

"We have to keep working because we had some difficult conditions in the morning."

Championship leader Rossi trailed in ninth, but the "Doctor" did not switch to a fresh set of tyres at the end of FP2 as did the majority of the riders.

The Italian, who will equal the all-time record of 328 Grand Prix starts on Sunday, preferred to work on his pace on used tyres.

Eighteen points separate Rossi and Lorenzo in the championship standings.

Rossi, 36, the seven-time world champion in the premier class, is chasing his first world title since 2009.
Source: AFP