Sebastian Vettel edged out Red Bull team-mate Mark Webber in the second practice at the Formula One Korean Grand Prix.
The reigning world champion was just 0.032 seconds ahead of Australian Webber but clocked in 0.328secs ahead of Ferrari's Fernando Alonso.
Korean GP Practice
F1 Grand Prix of Korea - Practice(01 of27)
YEONGAM-GUN, SOUTH KOREA - OCTOBER 12: Lewis Hamilton of Great Britain and McLaren drives during practice for the Korean Formula One Grand Prix at the Korea International Circuit on October 11, 2012 in Yeongam-gun, South Korea. (Photo by Mark Thompson/Getty Images) (credit:Getty Images)
AUTO-PRIX-KOR-F1(02 of27)
McLaren Mercedes driver Jenson Button of Britain speeds up during the second practice session of the Formula One Korean Grand Prix in Yeongam on October 12, 2012. AFP PHOTO/ROSLAN RAHMAN (Photo credit should read ROSLAN RAHMAN/AFP/GettyImages) (credit:Getty Images)
AUTO-PRIX-KOR-F1(03 of27)
Sauber driver Sergio Perez of Mexico looks on while course crews push his car away after having engine problems during the second practice session of the Formula One Korean Grand Prix in Yeongam on October 12, 2012. AFP PHOTO/ROSLAN RAHMAN (Photo credit should read ROSLAN RAHMAN/AFP/GettyImages) (credit:Getty Images)
AUTO-PRIX-KOR-F1(04 of27)
Course crews remove Sauber's driver Sergio Perez of Mexico race car after it suffered engine problems during the second practice session of the Formula One Korean Grand Prix in Yeongam on October 12, 2012. AFP PHOTO/ROSLAN RAHMAN (Photo credit should read ROSLAN RAHMAN/AFP/GettyImages) (credit:Getty Images)
AUTO-PRIX-KOR-F1(05 of27)
McLaren Mercedes driver Lewis Hamilton of Britain speeds up during the second practice session of the Formula One Korean Grand Prix in Yeongam on October 12, 2012. AFP PHOTO/ROSLAN RAHMAN (Photo credit should read ROSLAN RAHMAN/AFP/GettyImages) (credit:Getty Images)
F1 Grand Prix of Korea - Practice(06 of27)
YEONGAM-GUN, SOUTH KOREA - OCTOBER 12: Jenson Button of Great Britain and McLaren drives during practice for the Korean Formula One Grand Prix at the Korea International Circuit on October 11, 2012 in Yeongam-gun, South Korea. (Photo by Mark Thompson/Getty Images) (credit:Getty Images)
AUTO-PRIX-KOR-F1(07 of27)
Ferrari driver Felipe Massa of Brazil speeds up during the second practice session of the Formula One Korean Grand Prix in Yeongam on October 12, 2012. AFP PHOTO/ROSLAN RAHMAN (Photo credit should read ROSLAN RAHMAN/AFP/GettyImages) (credit:Getty Images)
F1 Grand Prix of Korea - Practice(08 of27)
YEONGAM-GUN, SOUTH KOREA - OCTOBER 12: Jenson Button of Great Britain and McLaren drives during practice for the Korean Formula One Grand Prix at the Korea International Circuit on October 11, 2012 in Yeongam-gun, South Korea. (Photo by Mark Thompson/Getty Images) (credit:Getty Images)
F1 Grand Prix of Korea - Practice(09 of27)
YEONGAM-GUN, SOUTH KOREA - OCTOBER 12: Jenson Button of Great Britain and McLaren drives during practice for the Korean Formula One Grand Prix at the Korea International Circuit on October 11, 2012 in Yeongam-gun, South Korea. (Photo by Mark Thompson/Getty Images) (credit:Getty Images)
F1 Grand Prix of Korea - Practice(10 of27)
YEONGAM-GUN, SOUTH KOREA - OCTOBER 12: Jenson Button of Great Britain and McLaren drives during practice for the Korean Formula One Grand Prix at the Korea International Circuit on October 11, 2012 in Yeongam-gun, South Korea. (Photo by Mark Thompson/Getty Images) (credit:Getty Images)
F1 Grand Prix of Korea - Practice(11 of27)
YEONGAM-GUN, SOUTH KOREA - OCTOBER 12: Jenson Button of Great Britain and McLaren drives during practice for the Korean Formula One Grand Prix at the Korea International Circuit on October 11, 2012 in Yeongam-gun, South Korea. (Photo by Mark Thompson/Getty Images) (credit:Getty Images)
F1 Grand Prix of Korea - Practice(12 of27)
YEONGAM-GUN, SOUTH KOREA - OCTOBER 12: Michael Schumacher of Germany and Mercedes GP drives during practice for the Korean Formula One Grand Prix at the Korea International Circuit on October 11, 2012 in Yeongam-gun, South Korea. (Photo by Mark Thompson/Getty Images) (credit:Getty Images)
F1 Grand Prix of Korea - Practice(13 of27)
YEONGAM-GUN, SOUTH KOREA - OCTOBER 12: Michael Schumacher of Germany and Mercedes GP drives during practice for the Korean Formula One Grand Prix at the Korea International Circuit on October 11, 2012 in Yeongam-gun, South Korea. (Photo by Mark Thompson/Getty Images) (credit:Getty Images)
AUTO-PRIX-KOR-F1(14 of27)
Ferrari driver Fernando Alonso of Spain (R) and his teammate Felipe Massa of Brazil (C) walk together at the paddock after a drivers' meeting for the Formula One Korean Grand Prix in Yeongam on October 12, 2012. AFP PHOTO / JUNG YEON-JE (Photo credit should read JUNG YEON-JE/AFP/GettyImages) (credit:Getty Images)
F1 Grand Prix of Korea - Practice(15 of27)
YEONGAM-GUN, SOUTH KOREA - OCTOBER 12: Nico Rosberg of Germany and Mercedes GP drives during practice for the Korean Formula One Grand Prix at the Korea International Circuit on October 11, 2012 in Yeongam-gun, South Korea. (Photo by Mark Thompson/Getty Images) (credit:Getty Images)
F1 Grand Prix of Korea - Practice(16 of27)
YEONGAM-GUN, SOUTH KOREA - OCTOBER 12: Nico Rosberg of Germany and Mercedes GP drives during practice for the Korean Formula One Grand Prix at the Korea International Circuit on October 11, 2012 in Yeongam-gun, South Korea. (Photo by Mark Thompson/Getty Images) (credit:Getty Images)
F1 Grand Prix of Korea - Practice(17 of27)
YEONGAM-GUN, SOUTH KOREA - OCTOBER 12: Nico Rosberg of Germany and Mercedes GP drives during practice for the Korean Formula One Grand Prix at the Korea International Circuit on October 11, 2012 in Yeongam-gun, South Korea. (Photo by Mark Thompson/Getty Images) (credit:Getty Images)
AUTO-PRIX-KOR-F1(18 of27)
McLaren-Mercedes driver Jenson Button of Britain (L) and Force India-Mercedes driver Paul Di Resta of Britain (R) walk together at the paddock after a drivers' meeting for the Formula One Korean Grand Prix in Yeongam on October 12, 2012. AFP PHOTO / JUNG YEON-JE (Photo credit should read JUNG YEON-JE/AFP/GettyImages) (credit:Getty Images)
F1 Grand Prix of Korea - Practice(19 of27)
YEONGAM-GUN, SOUTH KOREA - OCTOBER 12: Kimi Raikkonen of Finland and Lotus drives during practice for the Korean Formula One Grand Prix at the Korea International Circuit on October 11, 2012 in Yeongam-gun, South Korea. (Photo by Mark Thompson/Getty Images) (credit:Getty Images)
F1 Grand Prix of Korea - Practice(20 of27)
YEONGAM-GUN, SOUTH KOREA - OCTOBER 12: Kimi Raikkonen of Finland and Lotus drives during practice for the Korean Formula One Grand Prix at the Korea International Circuit on October 11, 2012 in Yeongam-gun, South Korea. (Photo by Mark Thompson/Getty Images) (credit:Getty Images)
AUTO-PRIX-KOR-F1(21 of27)
Red Bull-Renault driver Sebastian Vettel of Germany (L) signs his autograph to South Korea course crews at the paddock after a drivers' meeting for the Formula One Korean Grand Prix in Yeongam on October 12, 2012. AFP PHOTO / JUNG YEON-JE (Photo credit should read JUNG YEON-JE/AFP/GettyImages) (credit:Getty Images)
F1 Grand Prix of Korea - Practice(22 of27)
YEONGAM-GUN, SOUTH KOREA - OCTOBER 12: Paul di Resta of Great Britain and Force India drives during practice for the Korean Formula One Grand Prix at the Korea International Circuit on October 11, 2012 in Yeongam-gun, South Korea. (Photo by Mark Thompson/Getty Images) (credit:Getty Images)
AUTO-PRIX-KOR-F1(23 of27)
Mercedes-AMG driver Nico Rosberg of Germany performs a pit stop during the second practice session of the Formula One Korean Grand Prix at the Korean Circuit in Yeongam on October 12, 2012. AFP PHOTO / Philippe Lopez (Photo credit should read PHILIPPE LOPEZ/AFP/GettyImages) (credit:Getty Images)
F1 Grand Prix of Korea - Practice(24 of27)
YEONGAM-GUN, SOUTH KOREA - OCTOBER 12: Nico Hulkenberg of Germany and Force India drives during practice for the Korean Formula One Grand Prix at the Korea International Circuit on October 11, 2012 in Yeongam-gun, South Korea. (Photo by Mark Thompson/Getty Images) (credit:Getty Images)
F1 Grand Prix of Korea - Practice(25 of27)
YEONGAM-GUN, SOUTH KOREA - OCTOBER 12: Romain Grosjean of France and Lotus drives during practice for the Korean Formula One Grand Prix at the Korea International Circuit on October 11, 2012 in Yeongam-gun, South Korea. (Photo by Mark Thompson/Getty Images) (credit:Getty Images)
F1 Grand Prix of Korea - Practice(26 of27)
YEONGAM-GUN, SOUTH KOREA - OCTOBER 12: Romain Grosjean of France and Lotus drives during practice for the Korean Formula One Grand Prix at the Korea International Circuit on October 11, 2012 in Yeongam-gun, South Korea. (Photo by Mark Thompson/Getty Images) (credit:Getty Images)
F1 Grand Prix of Korea - Practice(27 of27)
YEONGAM-GUN, SOUTH KOREA - OCTOBER 12: Sergio Perez of Mexico and Sauber F1 drives during practice for the Korean Formula One Grand Prix at the Korea International Circuit on October 11, 2012 in Yeongam-gun, South Korea. (Photo by Mark Thompson/Getty Images) (credit:Getty Images)
Britain's Jenson Button came in at fourth while fellow McLaren driver Lewis Hamilton finished a disappointing eighth having been fastest in the first practice session.
Michael Schumacher, who announced he would retire for a second time at the end of the current season last week, finished a credible fifth ahead of Saturday's qualifying session.