George Russell is 84 points behind Mercedes team-mate Kimi Antonelli in the drivers' championship

George Russell says he will be taking a further grid penalty this season in addition to the one he has been hit with for this weekend's Singapore Grand Prix.

The Briton will start Sunday's race from the back of the grid because he needs to fit a new engine which takes him beyond his permitted number for the season.

But he says that he will have to take another new engine, as soon as a planned upgrade is ready, to get him to the end of the season.

Russell said: "You get (a limit of) four engines a season, so six races on each, and we have seven races to the end. So I will be taking another penalty, so yeah it's pretty relentless at the moment."

Russell's engine failure in Malaysia scuppered Mercedes' previous plan for him to last out with his older engine until the upgrade was ready, most likely for the next race, the United States Grand Prix in Austin.

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Russell to start from back of Singapore grid after penalty

"I knew I was going to have a penalty," Russell said. "The plan was always to go in Austin, and obviously Singapore is the second hardest track to overtake on on the calendars. So you would never choose to do it (here).

"But we have no engines because of all of the various failures, so there was no engine I could have reverted to from earlier in the season. With the failure I had to take it.

"We don't have the (upgrade) this weekend, and because there are seven races remaining, you can either choose to roll the dice and hope it lasts for seven races, but also suffer a performance offset (as the engine degrades), or just accept I'll be taking another penalty."

Antonelli will also likely have another back-of-the-grid penalty when the upgraded engine is introduced, following his previous one at the Italian Grand Prix, which he won from 19th on the grid.

Russell will also be reverting to an older specification car in Singapore this weekend.

Mercedes introduced an aerodynamic upgrade in Malaysia last weekend, but it did not give the car the performance uplift expected.

So in an attempt to prove whether that was because of idiosyncrasies to do with the Sepang track or a problem with the upgrade itself, Mercedes is splitting the specification of their cars.

Russell will drive the specification with which he won in Azerbaijan, the week before Malaysia, while Antonelli will run the new spec.

Russell said: "I actually asked a question already on Friday in Sepang. At the end of the day it's the car I'm reverting to is a car that was on pole by 0.8secs and Kimi won the race before, so it's important to remember the context. It's not like reverting back to a launch car.

"Given the circumstances of the grid penalty as well, it just seemed like a no-brainer. For me, unfortunately we're not going to be fighting for a podium this weekend, it's exceptionally unlikely, so it's more important for us to try and understand, was Malaysia a one-off or was it the upgrade?"

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Russell's retirement in Malaysia, along with Antonelli finishing second to Red Bull's Max Verstappen, meant the Italian's lead in the drivers' championship has extended to 84 points.

Both Mercedes drivers have suffered reliability problems this year but Russell believes his season has been disproportionately affected by factors outside his control.

"I've probably had more failures this year than I've had in the three seasons put together, and of course it's tough to take," he said.

"If I'm being 100% fair with myself, as I've said before, the performance this season hasn't been strong enough, and it probably would have affected me more if I'd have still been in the fight.

"But obviously the pressure and the momentum, every setback has an impact on that momentum.

"Since the start of the year (an engine failure) in Canada was the big one, and then, you know, the drive-through penalty in Monaco. The loss at the weekend has basically compromised two weekends for me.

"Two races, Silverstone and Spa, with the PU issues we had (involving a loss of performance from the engine), it's been pretty incredible how things have panned out this year, but I think just focus on what you can control."

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