Valtteri Bottas was running second before pitting on lap 31, but wouldn't exit the pits after a Mercedes pit-stop nightmare; Bottas: "It's disappointing. I couldn't believe it was happening"
Monday 24 May 2021 07:00, UK
Mercedes say the bizarre pit-stop retirement of Valtteri Bottas at the Monaco GP was due to a damaged wheelnut on his tyre, with the Finnish driver urging his team to learn from the incident.
Bottas was running second behind Max Verstappen when he pitted for fresh tyres on lap 31 of 78, but a slow pit-stop soon turned into a race-ending one as Mercedes couldn't remove his front right tyre.
The team explained that the "wheel nut machined onto the axle", essentially meaning it cross-threaded, with the tyre then unable to be removed.
"The nut was damaged to the point where it was never going to come off so we had no option but to park the car," said Mercedes trackside engineering director Andrew Shovlin.
Team boss Toto Wolff added that it had "never happened to that extent before" and was "something we need to understand".
Mercedes had a double blow on Sunday in Monaco, with the pit-stop disaster as well as a poor race for Lewis Hamilton, who finished a lowly seventh and lost his lead of the championship to race-winner Verstappen.
Bottas, meanwhile, was left ruing another day of misfortune in the Mercedes car.
The Finn had been by far the quickest Mercedes all weekend, but leaves round five having dropped more points to Verstappen and Hamilton, and is now fourth in the championship.
"If it's a technical issue, we need to get on top of it and make sure it never happens again," said Bottas. "It's disappointing. I couldn't believe it was happening."
A pit-stop is usually around two seconds long, but Bottas quickly started to understand this was not the standard stop.
"It felt like forever," he added. "I was counting, like now maybe we lost a place to [Carlos] Sainz, then probably to [Lando] Norris, then I knew it was going to be hard... but I think I've never had it where actually the race is over because of that.
"Learning needs to happen from this day."