Vettel tops timesheets in Korea
Lewis Hamilton found himself scuppered in his bid for a clean sweep of practice ahead of the Korean Grand Prix as Sebastian Vettel took the honours in the final session.
For the first time this season Hamilton finished top of the timesheet on a Friday, declaring himself happier than he has been all year with his Mercedes at the end of the two 90-minute sessions.
Yet in the closing hour-long outing ahead of qualifying, when drivers generally crank up the pace, Hamilton barely improved, shaving three tenths of a second off his time from Friday to finish fourth.
Instead, it was Vettel who made the most gains as Red Bull's triple world champion was quicker by almost a second compared to his time on Friday.
Around the Korea International Circuit, Vettel clocked a lap of one minute 37.881secs, with only team-mate Mark Webber for company, the Australian finishing 0.137secs adrift.
Qualifying will undoubtedly be a battle again between Red Bull and Mercedes, with the latter duo third and fourth as even Nico Rosberg managed to get his nose in front of Hamilton.
The German finished 0.437secs behind compatriot Vettel, with Hamilton just 14 thousandths of a second further back.
As for Ferrari's Fernando Alonso, the only realistic challenger to Vettel as he trails by 60 points, the Spaniard was fifth quickest, down by six tenths of a second.
Team-mate Felipe Massa was seventh, providing the filling in a Lotus sandwich as Romain Grosjean and Kimi Raikkonen were sixth and eighth, with the latter almost a second off of Vettel.
Sauber's Nico Hulkenberg and Jenson Button in his McLaren, wearing new overalls that are 100 grams lighter, were ninth and 10th, with the Briton 1.233secs off the pace.
Force India's Paul Di Resta was down in 16th, almost 1.5secs back, with Marussia's Max Chilton again at the back of the pack, 4.386secs adrift.