Toto Wolff explains Lewis Hamilton’s struggles after Mercedes 'turn car upside down'

Toto Wolff says Mercedes “turned the car upside down” after enduring a difficult start to the F1 Singapore Grand Prix weekend.

Both Mercedes drivers were left puzzled by their lack of pace during Friday practice in Singapore, with George Russell ending the day seventh, while Lewis Hamilton only managed to go 11th.

Things improved during Saturday’s final practice ahead of qualifying, with Russell finishing second-quickest, nearly half a second down on the blistering pace set by McLaren’s Lando Norris.

Speaking to Sky Sports F1 after FP3, Wolff revealed Mercedes made big changes to their W15 challenger overnight.

“I think with these cars you never quite understand,” Wolff said.

“We turned the car upside down, literally. It seems to be in a much better balance window. The whole [FP3] classification was a bit odd.

“Lando so far ahead, then big spreads between teammates.”

Hamilton improved slightly to go seventh-quickest in FP3, though the seven-time world champion was well off Russell’s pace and 1.2s slower than Norris’s benchmark.

A downbeat Hamilton admitted on Friday that Mercedes were “just a bit lost” with their car’s set-up and predicted he would struggle to make it into Q3 in qualifying.

"The car feels very difficult. A very challenging day," Hamilton said after FP2. "We tried everything set-up wise and nothing seems to work with the set-up. Definitely very challenging.

"We are giving it everything then you find out you are a second off. Ultimately, just a bit lost. Not really sure where to put the car."

Asked why Hamilton still appeared to be struggling in FP3, Wolff explained: “They have a bit of a different set-up and we tried a few things in the session, so that’s not the gap you would normally have with the same car.”

Wolff added Hamilton’s gap to Russell was only “partially” understood.