McLaren are among those paying tribute following the announcement of the shock death of Gil De Ferran.
The 56-year-old was a sporting director at the team between 2018 and 2021 and had been acting at the Woking outfit in a consultant role.
According to the Brazilian Automobile Confederation (CBA), the former Indy500 winner suffered a heart attack at a private motor racing club in Opaa-locka in Florida on Friday.
Despite being 'promptly' taken to a local hospital he sadly did not survive.
McLaren said in a statement: "Everyone at McLaren Racing is shocked and deeply saddened to learn we have lost a beloved member of our McLaren family.
"Gil was an important and integral part of our Racing team. He was a formidable force on and off track and made a lasting impact on everyone racing and working alongside him."
F1 greats pay their respects
Former F1 star and compatriot Felipe Massa also paid tribute to De Ferran who previously also worked as a sporting director at BAR in a two-year role up until the summer of 2017.
"What sad news today. We lost a brother! Wonderful person and a legend in our motorsport world. Go in peace Gil," Massa said.
F1 legend and 1978 world champion Mario Andretti added: "My heart sank at the news of Gil de Ferran's death. It's heart-wrenching. Thinking of him now and savoring every conversation. He will be missed by so many. A wonderful man and a dear and loyal friend."
CBA president Giovanni Guerra said: "On behalf of myself and the entire CBA family, we pray to God to receive our brother with all glory and to support his family, friends and millions of fans around the world."
My heart sank at the news of Gil de Ferran's death. It's heart-wrenching. Thinking of him now and savoring every conversation. He will be missed by so many. A wonderful man and a dear and loyal friend. pic.twitter.com/aPVXjlKwY7