Toto Wolff feels Lewis Hamilton "saved" Mercedes at the Monaco Grand Prix and admitted the Formula 1 team was mistaken in switching to medium tyres during the safety car period.
Mercedes went it alone in moving on to the medium compound during the interruption, which came when the safety car was called out to allow marshals to clear debris left on the track from Charles Leclerc's flailing tyre.
The team decided against switching to hard tyres as the pursuing Red Bull and Ferrari teams did because it was concerned that a slow warm up could leave it vulnerable.
But with Hamilton suffering graining of his front tyres a few laps into his stint, it meant he had to manage his pace significantly and back-up the cars behind him to ensure he could make it to the finish.
When asked about the move to mediums, Wolff said that Mercedes had made the wrong call, but emphasised how much Hamilton's driving had bailed out the team.
"I had a chat with [strategist] James [Vowles] and obviously it was the wrong call," said Wolff.
"We thought the tyre would make it to the end but it didn't. He saved us - his driving saved us. It's something which we really need to analyse."
When Mercedes made the switch, the team felt that it would not be too difficult to get to the finish on the mediums.
But the graining that quickly emerged on Hamilton's front tyres soon changed the mood in the Mercedes pit.
"What was calculated was that the medium would make it, if we were to change on lap 15 or 16, with the right management," explained Wolff.
"So, being in the lead, that was a pretty straight strategy.
"It didn't even seem like a huge stretch, but we realised 20 laps into the race that on the left front some graining [had] appeared and he started to complain about the understeer that resulted from the graining.
"It was clear that it would get very, very difficult to make it to the end. "So we had quite some discussions about the tyre lasting another 40 laps, and I was reminded that it was only 20 laps of a normal circuit so calmed down a bit!
"But everybody knew that it was going to be a huge stretch and even probably 20 laps from the end he had 0% rubber left on the tyre with massive understeer on the slow speed.
"You could see around Loews [hairpin] the car wouldn't turn anymore."