George Russell was forced to replace his power unit ahead of the Hungarian Grand Prix when a crack in the engine caused a coolant leak during qualifying. The incident halted his final qualifying lap, leaving him with a disappointing seventh-place grid slot, although he will actually line up sixth after teammate Kimi Antonelli received a three-place grid penalty for a speeding infringement. During the closing moments of Q3, the Mercedes team detected a sudden drop in water pressure, prompting Russell to pull off the track. Engineers quickly identified a leak originating from a fissure in the power‑unit casing, a problem they believe was triggered when Russell rode over the exit kerb at Turn 4 on his last flying lap.
Because the replacement is for a unit of the same specification, the change does not count as a fifth engine for the 2026 season, meaning Russell avoids a further grid penalty despite taking his fourth power unit of the year. "We lost water pressure and I had a water leak. When I stopped on track, the car was leaking a load of water," Russell told Sky Sports F1. "Fingers crossed it doesn't affect anything for the race." The British driver, who trails championship leader Antonelli by 50 points, hopes the swap will not compromise his performance on Sunday.
Mercedes has been battling reliability concerns this season, with both of its drivers suffering engine‑related setbacks. Russell, in particular, was left "speechless" after the Belgian Grand Prix when a software glitch in the power unit stripped him of straight‑line speed, culminating in a race‑ending collision with Lewis Hamilton at Spa‑Francorchamps.
The team has since patched the software, and technical director Simone Resta explained that the issue was present in every car but hit George harder because Kimi was running a fresher engine package. "The software is the same for all the cars, and it was there in every car, but it affected George more than Kimi," Resta said.
"We also need to bear in mind that, when comparing their performance in the last few races, Kimi was on a fresher power unit, which is, of course, always a bit better than a quite used power unit. That will change in the next races when we start to have a fresher power unit on George's side.
So, there's a bit of everything. There's a bit of software, but there's also Kimi being out of phase with George's programme. You sum up everything when you look at the final result." The Hungarian circuit, with its mix of fast straights and tight corners, will test the new unit’s durability and the team's ability to optimise tyre performance.
Russell acknowledged that his qualifying pace had lagged behind Antonelli’s throughout the European swing, noting that the British driver’s car seemed more tyre‑constrained than mechanically limited. "We were probably even further on Friday but we had the strongest race pace, which tends to say it's not a car problem but a tyre problem," Russell explained. "Time will tell in the race if we struck the right balance between the qualifying setup and race setup.
We probably know we could make the car faster in qualifying trim at the expense of race performance. It's going to be difficult to overtake. It would have been nice to be higher up." Beyond the immediate technical drama, the weekend schedule is packed. The day begins with an F3 feature race at 7:35 am, followed by the Porsche Supercup at 9:05 am and an F2 feature race at 10:20 am.
The Hungarian Grand Prix build‑up starts at 12:30 pm, leading into the main race at 2:00 pm on Sky Sports F1 and Sky Sports Main Event. Post‑race analysis, including the chequered‑flag reaction and a segment called "Ted's Notebook," will air later in the afternoon. Viewers can also stream the coverage via NOW without a long‑term contract.
The starting grid, as confirmed after penalties, places Lando Norris (McLaren) on pole, followed by Charles Leclerc (Ferrari), Oscar Piastri (McLaren), Max Verstappen (Red Bull), Lewis Hamilton (Ferrari), George Russell (Mercedes), Kimi Antonelli (Mercedes), Isack Hadjar (Red Bull), Arvid Lindblad (Racing Bulls) and Nico Hülkenberg (Audi). While Russell hopes to claw back some of the 50‑point deficit to his teammate, he remains realistic about the challenges of breaking into the podium mix, especially given the recent reliability woes and the need to manage a freshly installed power unit. The Hungarian Grand Prix will therefore serve as a crucial litmus test for Mercedes' ability to recover from a string of mechanical setbacks.
If the new unit holds up and the team can fine‑tune the car’s setup for both qualifying speed and race durability, Russell could mount a respectable comeback. However, the combination of a water‑coolant leak, a recent software patch, and the inherent difficulty of overtaking at the Hungaroring means that any progress will require a flawless execution from driver and engineers alike.