by Richard Rae
Red Bull appear to be firm favourites for the Japanese Grand Prix after topping the timing sheets in both Friday's practice sessions.
Sebastian Vettel and Mark Webber ended second practice half a second faster than Renault's Robert Kubica.
Lewis Hamilton, who crashed out early in first practice, missed most of the second session waiting for his McLaren to be repaired.
However rain forecast for Saturday could turn qualifying into a lottery.
As during the morning session, conditions were warm and dry when the cars came out for second practice.
The main interest lay in whether Ferrari, having kept their race pace carefully hidden during first practice, could show they had the basic speed to mount a serious challenge Red Bull around Suzuka's sweeping high-speed corners.
There was also the question of how much running Hamilton could squeeze in after completing just nine laps before crashing out of first practice.
While the McLaren engineers worked frantically on Hamilton's car, Webber and Vettel swapped fastest laps on both the hard prime and soft option tyres.
With half an hour remaining Renault's Kubica was more than half a second adrift in third, with Ferrari's Fernando Alonso and team-mate Felipe Massa in fourth and fifth.
Required to shoulder the burden of the entire McLaren test programme, Jenson Button was sixth fastest. The teams settled into race runs, with Vettel's fastest time of 1.31.46 putting him four-tenths of a second clear of Webber, with 1.31.680, and Kubica on 1.32.20.
Only eight minutes remained when Hamilton finally emerged from the the pit-lane, with his McLaren on soft tyres, for a data-accumulating five lap run with a heavy fuel load. His fastest effort left him 13th, over two seconds behind Vettel. But with even Alonso almost a second off the pace, McLaren may not be the only team pinning their hopes on the weather giving them a gambler's chance in qualifying.
More to follow
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