Mercedes apologised to Lewis Hamilton for what they admitted was the strategic error that cost him victory in the Monaco Grand Prix.
Hamilton was leading when he was called in for fresh tyres during a late safety car period, dropping him to third.
Mercedes F1 boss Toto Wolff said: "The answer is we got the maths wrong.
"That one goes on the team and I apologise. He's a great leader and a great driver. I am sure he will understand sometimes we make errors."
The mistake handed victory to Hamilton's team-mate Nico Rosberg and also cost Hamilton a position to Ferrari's Sebastian Vettel.
It cut the world champion's advantage in the championship over Rosberg to 10 points.
Hamilton was visibly distraught afterwards, but refused to blame the team for the error.
After crossing the finish line, Hamilton slowed to a stop at the Portier corner - which faces out to the Mediterranean Sea - seemingly to gather his thoughts.
He then completed the lap and drew up to the podium, where he knocked over his 'third place' parking board with the front of his Mercedes.
Wolff said the error was made because of concerns that the tyres on the Mercedes were losing temperature and that they might be vulnerable in the event Vettel stopped under the safety car for fresh tyres.
The decision was made more difficult, he said, because the GPS tracking system that shows the positions of all the cars on track was not available in Monaco.
"We thought we had a gap which we didn't have when the safety car came out and Lewis was behind the safety car and the calculation was simply wrong.
"We expected to have a couple of seconds more."
Wolff refused to say who had made the final decision to pit Hamilton, who exited the pits almost side by side with Vettel, but had to cede position because the Ferrari got to the designated marker line fractionally ahead.
"It was the team's decision," Wolff said. "We are all in this together, we make decisions together and it is not one person to blame and we win and lose together and that is clear.
"From a common sense overview, disregarding the data I agree it looks like a risk. But we have to follow the data; that is how the sport works. But the simple answer is the numbers were wrong."