George Russell says a "serious issue" with the straight-line performance of his Mercedes is making his title fight with Kimi Antonelli "impossible".

George Russell will start the Belgian Grand Prix from third place because of a 10-place grid penalty for McLaren's Lando Norris George Russell says a "serious issue" with the straight-line performance of his Mercedes is making his title fight with team-mate Kimi Antonelli "impossible". Russell qualified fourth for the Belgian Grand Prix, and was 0.508 seconds slower than the 19-year-old Italian, who took his sixth pole position in 10 races. The Briton said that the majority of his deficit to Antonelli could be explained by a mystery lack of speed on the straights. "When I cross the line, you see you're half a second down, it feels pretty rubbish," Russell said. "But when you realise more than 75% of that's coming from the power-unit, you feel a bit better. "I was pleased with my lap. When I look at the corners, there's a lot of corners I was faster. There's definitely corners I needed to improve. But the corners look like a normal fight you'd have for a pole. The straights is not." Russell has been struggling for pace in comparison with Antonelli all weekend at the classic Spa-Francorchamps circuit in Belgium. He ended Friday practice more than a second adrift, and had been told by his team that the deficit was explained by the way he was driving the corners.