Belgian Grand Prix: Kimi Raikkonen tops practice as Massa crashes
Ferrari's Kimi Raikkonen was fastest in first practice at the Belgian Grand Prix ahead of title rivals Lewis Hamilton and Sebastian Vettel.
The Finn pipped Hamilton by just 0.053 seconds, with the Mercedes driver 0.092secs ahead of Vettel, who leads the championship by 14 points.
The three were 0.7secs clear of the field, Red Bull's Max Verstappen and Daniel Ricciardo in fourth and fifth.
Valtteri Bottas was sixth and Williams' Felipe Massa crashed early on.
The headline lap times appeared to understate what looked like a significant advantage for Hamilton over the Ferraris.
The Briton set his fastest lap on the hardest tyre option available this weekend, the 'soft', while Raikkonen and Vettel used the softest, the so-called 'ultra-soft'.
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There would be expected to be a lap-time difference of at least a second between the two types of tyre.
On top of that, Hamilton was 0.5secs slower through sector one on his fastest lap than his own best time through that section of track - the La Source hairpin and the daunting 200mph Eau Rouge swerves.
That suggests his potential fastest lap was at least one minute 45.0 seconds - Raikkonen's best was 1:45.502.
It was an incident-packed session, starting from an early crash for Massa, who lost control over the kerb at Malmedy, the right-hander after the Les Combes chicane at the top of the long straight.
The Brazilian speared straight into the barriers and badly damaged the left-hand side of his car, bringing the session to a halt for 10 minutes.
He will need a new chassis for the rest of the weekend, and it is doubtful whether the car will be ready to take part in second practice, which starts at 13:00 BST.
Later on, Bottas had an unusual incident, when on a slow lap he lost control at the Fagnes chicane while off line and trying to let another car by.
Bottas slid off into the gravel trap, damaging his front wing, but managed to rejoin and get the car back to the pits.