Vettel leads a Ferrari 1-2 in final Belgian GP dress rehearsal

Spa is bracing for a thrilling qualifying session Saturday afternoon following another impressive performance from Ferrari and Sebastian Vettel in the third free practice session.

The German driver concluded the morning fastest by 0.063s, shadowing team mate Kimi Raikkonen and Mercedes' Lewis Hamilton and Valtteri Bottas.

Belgian Grand Prix - Free Practice 3 times

Teams were greeted with overcast and menacing skies over Spa on Saturday morning, but the final free practice session got underway on a dry track despite a bout of rain earlier in the day.

McLaren's duo of Fernando Alonso and Stoffel Vandoorne were quick to take to the track, with both cars running in close contention as the Spaniard was perhaps trying to help his troubled team mate extract more speed from his MCL33.

Vandoorne wasn't happy after yesterday's reliability issues, suggesting his team needed to get on top of reliability problems almost always impacting the Belgian this season.

After Ferrari's domination of Friday's sessions, Kimi Raikkonen and Sebastian Vettel unsurprisingly positioned themselves in the top runners early on, the Finn establishing a reference time of 1m43.425s using the supersoft tyre.

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It's worth noting that both SF71-H's have benne fitted with Maranello's spec-3 engine, providing an additional boost to their drivers.

Bottas - a man who will have his work cut out for him tomorrow when he launches his race from the back of the grid as a result of his engine penalty - slotted himself between the two red cars, albeit while using a harder tyre.

As the session approached the 30-minute mark Hamilton caught up and overhauled his team mate, but remained 0.098s adrift from Raikkonen, while Max Verstappen and Daniel Ricciardo finally got themselves up to speed, placing their Red Bulls respectively fifth and sixth, but with the Dutchman a second clear of his team mate.

As the session rushed to its close, everyone upped the pace, building up their speed for qualifying.

Raikkonen got down to 1m42.734s, just edging Vettel, but the German then put in an effort worth a lap in 1m42.661 that put him at the top of the board.

Shod now with supersoft rubber, Mercedes' chargers made an attempt to challenge the Ferrari duo's leadership. To no avail however as Hamilton and Bottas remained behind.

With ten minutes to go, Vandoorne brought out the red flag after spinning on the Kemmel straight. Replays showed the Belgian trying to pass a slower Bottas on the left side but getting squeezed on to the track by the Mercedes driver who obviously did not see the McLaren coming up from behind.

It was likely a case of poor communication in the Silver Arrows camp although one could argue that Vandoorne put himself at risk by keeping his foot down and choosing to overtake the Finn on the racing line.

The aborted end to the session precluded most drivers from undertaking any qualifying simulations.

It will still be a thrilling hour to look forward to this afternoon however, with Ferrari appearing to have the upper hand over Mercedes. At least for now.

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