Toto Wolff has revealed Mercedes kept George Russell in the dark over a reliability problem that threatened to derail his bid for a maiden F1 victory.
Russell scored a dominant win at the São Paulo Grand Prix to end Mercedes' drought and ensure the team did not register its first season without topping the podium since 2011.
The 24-year-old had come close to a win two years ago with Mercedes when deputising for Covid-struck Lewis Hamilton at the Sakhir Grand Prix in Bahrain, only for a blunder in the pits and a puncture to deny him.
Asked if this victory was redemption for the previous near-miss, Wolff said: "I don't know if it's redemption. I think he deserved to win in Bahrain and we let him down with the car.
"And that's why this victory makes us happy because he could have had one on the clock two years ago and he didn't, and now he has that first victory.
"As an aside, we had a water leak on the car throughout the race and it wasn't clear whether we could actually make it to the end."
Mercedes confirmed the problem manifested at around half-race distance and that Russell had not been informed during the 71-laps.
Revealing the extent of the problem, a spokesperson explained: "We were concerned at one point that we would be four-five laps from the finish and not make it. But then it did but by the skin of its teeth."
Wolff, who was absent for only the third time since assuming his position with Mercedes and missed a victory for the first time, added: "We talked about it on the intercom and we all agreed we were going to let him drive to the end even without water, just on whatever was there and try to finish the race."