Mercedes were close to halting Nico Rosberg's charge at the season-opening Australian GP due to rising brake temperatures in the W07.
Rosberg took advantage of an error from team-mate Lewis Hamilton at the start, and Ferrari in their tyre strategy, to claim the first victory of 2016 and extend his winning streak to four races.
But both Toto Wolff and Rosberg have admitted his car was almost retired after debris was caught in the brake caliper.
"Managing tyres and temperatures became a big challenge, with debris causing an overheating brake caliper that almost forced us to retire Nico at one stage," Silver Arrows chief Wolff said.
"Thankfully that was not the case and he led Lewis home for a hard-fought 1-2."
Rosberg, who conducted a live interview via Periscope on the flight home from Melbourne on Sunday, said: "The brakes were on the limit today, it was really tough.
"They were about to retire me, so I was just managing it myself to the limit - but it was close."
The German started the race behind pole-sitter Hamilton and while he was overtaken by the Ferraris off the line, he forced the world champion off the track at Turn One and was able to keep the pressure on Sebastian Vettel.
The red flag following Fernando Alonso's horror crash at Albert Park resulted in a shift in strategy and momentum, with Ferrari opting for supersoft tyres while Mercedes kept their two drivers on the medium compound. Rosberg, able to complete 39 laps on the tyre and finish the race, didn't have to overtake a single car all afternoon and closest rival Hamilton was eight seconds down the road at the chequered flag.
"It's been a great day, a fantastic day," Rosberg added on the plane. "It was a tough race. The start was OK but Sebastian got me. He did a great job into Turn One. I was committed but he broke later and I lost a place to Kimi - then the race was on.
"From the red flag we put on the right tyres. We gambled with the mediums and I don't think Ferrari made the right choice. I could go to the end and I knew Sebastian had to stop again so that gave me the win."
Rosberg said he was joined by "the whole of F1" on his flight, often panning to Vettel during the chat. He joked: "Who snores the worst on the plane? Probably Sebastian, so I've taken a seat very far away from him."
Don't miss the F1 Report for all the reaction and analysis from the Australian GP. Natalie Pinkham is joined by David Brabham and former McLaren mechanic Marc Priestley on Wednesday at 8:30pm on Sky Sports F1.