F2 Hungary: clutch issue caused feature race retirement

Russell was due to start fourth after a problem with getting his tyres up to temperature in qualifying denied him a shot at pole, but he failed to take his spot on the grid after encountering the problem on his way to the grid.

"When I came into the pitlane for the first installation lap, I went to take the clutch [and] it made a terrible screeching noise and the car wasn't stopping," Russell told Autosport.

"I had to put it in neutral and then I couldn't get back into first.

"We thought we'd fixed the problem by changing a sensor, but the problem was still there.

"As the race progressed it got worse and wouldn't allow me to stop - the clutch was fully closed.

"It's a shame. It's the second time this year we've had a mechanical before the race has even started, but it's motor racing. It's just one of those things.

"[But] we're still leading the championship, the car is still really quick - [I] still fully believe I can win this thing.

"I'm not too disheartened. We have a fantastic chance."

Lando Norris, Russell's chief title rival in 2018, took second in the race, cutting the gap between the pair to 19 points.

Norris will start seventh in Sunday's sprint race, while Russell will line-up at the back of the grid.

"I think since Baku, taking out Monaco, which you could call a joker as the engine failed in practice, we've arguably been the quickest at every track," Russell added.

"Obviously, we didn't put it on pole yesterday, but the pace was there, and I think we're extremely quick at the moment.

"We're leading by 19 points, but I feel we should be much further ahead."

F2 has introduced a new clutch for its new-for-2018 car this weekend, which resulted in no failed race starts for the first time this season.