George Russell isn’t running the theoretically faster Mercedes upgrade package at this weekend’s Formula 1 Singapore Grand Prix, something Russell first suggested.

Russell’s retirement in Malaysia means he’ll take a grid penalty this weekend for engine component changes, but he’ll also be running a very different aerodynamic specification to team-mate Kimi Antonelli.

That’s because Russell’s Mercedes has been rolled back to before the upgrade was introduced in Malaysia last weekend.

After its confusing debut, Mercedes had left the door open to splitting its drivers across the old and new packages for Singapore, something it confirmed on Wednesday, but on Thursday, Russell revealed he’d actually “instigated the conversation prior to the race on Sunday” in Malaysia.

“So when the failure happened, it was kind of a no-brainer because we were kind of 50-50 about it pre-race, and I was more in favour to do it, and that was even pre-race, whereas now, it is a total no-brainer,” Russell added.

Singapore is a crucial weekend for Mercedes to understand its new upgrade package. There hasn’t been anything in its data to suggest it’s not working as expected, but it was convincingly beaten by Red Bull in Malaysia.

The Malaysia upgrade was Mercedes’ first major package since the Canadian GP in May.

“There’s no signs telling us the upgrade was not working and we know the car we had in Baku was the same car as we had in Budapest and Zandvoort and in Baku we were on pole by eight tenths and in Budapest we were four tenths off the pace,” Russell said.

“So those fluctuations, even with a consistent car and your rivals with the same car, are drastic; you have a fluctuation, plus or minus one second can be that delta.

“So we’re pretty confident it’s Malaysia-specific. When you look at the pace of Red Bull, they clearly overperformed compared to where they’ve been this season, compared to all of the other teams.

“Actually, when you look at our pace compared to McLaren and Ferrari, it wasn’t too dissimilar.

“This engine penalty this weekend has given us a good opportunity to roll back, it’s a car that I’ve won in Baku with. So let’s see.”

Singapore being a sprint weekend means it wouldn’t be practical for Mercedes to run the new and old packages back-to-back in FP1-only and then switch both drivers onto the same spec for sprint qualifying.

So both Antonelli (new) and Russell (old) are essentially locked in for the Singapore weekend.

Mercedes needs answers on its upgrades because important 2027 car decisions need to be made, which will be informed by whether the upgrade is shown to be a real-world improvement.

The key questions are whether the low-speed performance deficit in Malaysia that hurt it was track-specific or upgrade-specific, and whether the lack of straightline speed there was a consequence of the new package.

A weekend-long back-to-back test is the best way to get those answers quickly, as it can’t afford to come out of this triple-header without them.

Its comfortable position in both championships – 106 ahead of the top non-Mercedes in drivers’ and 151 points over Ferrari in the constructors’ – also means it can afford to sacrifice a bit of ultimate performance across its cars this weekend.

Mercedes couldn’t fast-track ADUO

With Russell needing a new power unit, Mercedes assessed whether it could bring forward the debut of its planned ADUO 2 (Additional Development and Upgrade Opportunities) upgrade from the US GP to Singapore.

But it’s not ready in time, so Russell will have to take an additional grid penalty after Singapore before the end of the season, a “double whammy” in the words of Mercedes deputy F1 team boss Bradley Lord.

Russell said: “The engine [that failed in Malaysia] wasn’t stretched too long. It was the sixth race of the engine and obviously you have four engines a year, six races per engine when you split it up.

“We actually put that engine in on Sunday in Budapest so it was actually the sixth race but minus qualifying and the practice sessions in Budapest.

“We were waiting to take the engine penalty with the ADUO update, but obviously unfortunately we’ve had to take it here.

“But with seven races remaining, that’s longer than the engines are designed for and unfortunately it means I’ll be taking another penalty at some point between the next race and the end of the season.

“So yeah, it feels a little bit one thing after another right now, but that’s just how the cookie crumbles.”

Russell sits 84 points behind Antonelli with seven races to go.