Pietro Fittipaldi underwent a successful operation on Friday night after his high-speed crash during qualifying for the FIA World Endurance Championship curtain-raiser at Spa.
The Brazilian driver was airlifted to hospital after suffering what were suspected to be fractures in both his legs when he crashed at Eau Rouge in the #10 DragonSpeed BR Engineering BR1-Gibson.
Fittipaldi, who had been due to make his WEC debut this weekend standing in for Renger van der Zande, was subsequently operated on and remains in hospital in the nearby city of Liege.
A WEC statement issued on Saturday morning read: "Pietro Fittipaldi is well and his condition is stable.
"He was operated on last night for fractures to both his legs, and the operation went well. He remains under observation at the Centre Hospitalier de la Citadelle de Liege.
"The left leg, which suffered a complex fracture, has been satisfactorily operated upon. Pietro was completely conscious on exiting the Operating Suite and was able to describe what happened to him.
"At 10:30 [CET] today he left intensive care. His father was with him throughout the night."
According to Fittipaldi's father Gugu da Cruz, the 21-year-old is expected to be out of racing action for eight weeks, ruling him out of his planned Indianapolis 500 debut this month with Dale Coyne Racing.
He made his IndyCar debut in Phoenix last month and was also scheduled to contest the GP of Indy, as well as Texas, Mid-Ohio, Portland and Sonoma later in the year.
His next scheduled Super Formula race for Team LeMans is at Fuji in early July.
Chassis damage and a lack of available substitutes for Fittipaldi mean DragonSpeed will not take part in the Spa WEC opener, reducing the LMP1 field to seven cars.
Additional reporting by Erick Gabriel