Mercedes boss Toto Wolff revealed the team came close to retiring Nico Rosberg before the German went on to win the Australian Grand Prix.
Rosberg finished ahead of team-mate and defending Formula One champion Lewis Hamilton to take the chequered flag in the season-opening race, sealing his 15th career F1 victory.
However, Rosberg almost did not make the finish line in Melbourne, with Wolff admitting the 30-year-old came very close to retirement.
"We had a problem on Nico's car with brake caliper temperatures which kept creeping up, almost to a stage where we thought about retiring the car," Wolff said.
"That was two-thirds into the race. It was from debris we caught in the caliper.
"Then it stabilised at maximum value. And then it started to creep down again, very slowly, and recovered. [At] a certain stage, it was very difficult for the team to handle."
He added: "[Nico] didn't know. You can't tell him. The alarm would come up [if it was dangerous], but we were really super close to that and there's nothing you can do about it."