|McLaren's Lewis Hamilton makes a splash during practice for the Korean Grand Prix [GALLO/GETTY]
Lewis Hamilton aimed to end Red Bull's run of pole positions after leading Jenson Button to a McLaren one-two in South Korea on Friday in practice for his team's 700th Formula One race.
The 2008 world champion, who has been questioning his performances after five straight races without a podium finish, lapped a wet Yeongam circuit with a best time of one minute 50.828 seconds in the afternoon.
Red Bull, who have already won the drivers' title for the second year running with 24-year-old German Sebastian Vettel, have started every race this season on pole position.
Hamilton, who has not taken the top slot for more than a year, hoped to end that on Saturday.
"It would be great to get the pole here tomorrow," he told reporters.
"On a Friday we don't know what they are doing so today doesn't mean anything. But I think we are quick. I think our car was good"
"On a Friday we don't know what they are doing so today doesn't mean anything. But I think we are quick. I think our car was good.
"Jenson showed in the last race that we can be very, very competitive, so I have no doubt that we will be out to challenge them. Whether or not we can outdo them in qualifying, which has not been done all year, will be interesting."
Button, winner of the previous race in Japan and chasing his sixth successive appearance on the podium, was 0.104 slower in the second 90-minute session and struggled to get heat into his car's front tyres.
The 2009 champion, whose style is notably smoother than his more aggressively steering team mate, said there was a lot more work to do.
Mercedes Michael Schumacher lived up to his fame as a master of wet conditions with the fastest time of 2:02.784 in the opening session.
"Today was one of those Fridays where most of what you do is race preparation, knowing that the conditions will probably be totally different when it comes to Sunday," said the seven-times champion.
Vettel, back on track for the first time since he became Formula One's youngest double champion in Japan, was second and third respectively in the sessions.
"For Saturday and Sunday the weather forecast is dry, so whatever we learned today might not be worth a lot this weekend," said the German.
"It's a tough track for tyres here, even though you have a long straight."
Hamilton's time will have boosted his spirits after Button was quicker in all three practice sessions in Japan.
The Briton told reporters earlier that he felt he had fallen off "quite a steep cliff" since he last won in Germany in July.
| Sebastian Vettel looks over at Lewis Hamilton, the man most likely to challenge his crown [GALLO/GETTY]
Six drivers, including Button, did not set timed laps in the morning as the rain fell steadily and made track conditions treacherous.
Even Schumacher's sure touch failed him momentarily when he skidded on to the grass at the pit-lane entry.
There were more spins and slides in the afternoon, with Schumacher's team mate Nico Rosberg running wide braking into the tight left-handed first corner and spearing into Jaime Alguersuari's Toro Rosso as the Spaniard exited the pit lane.
The accident revived driver concern about the position of the exit.
With the grandstand largely empty and conditions resembling those on race day a year ago when the start had to be delayed, the few fans venturing to the track some 320km south of Seoul saw little action until after lunch.
Young French test driver Jean-Eric Vergne took part in practice with Toro Rosso while Indians Narain Karthikeyan and Karun Chandhok, both hoping to race in their home grand prix this month, turned out for HRT and Team Lotus respectively.