Felipe Massa remains in a stable condition in the AEK hospital in Budapest this morning, as doctors and Ferrari were left encouraged that there had been no further complications overnight.
Massa underwent successful surgery yesterday afternoon as a result of the skull fracture and brain concussion he suffered in a crash at Turn 4 during qualifying at the Hungaroring after he was hit on the head by a spring from Rubens Barrichello's car.
As is standard procedure for such operations, Massa was put into an induced coma and remained under observation in intensive care at the hospital.
A statement issued by Ferrari on Sunday morning said: "After undergoing an operation yesterday afternoon, Felipe Massa's condition remains stable and there were no further complications through the night.
"He will be given another CT scan today, which will provide more precise information."
Sources have told AUTOSPORT that the doctors at the hospital are 'optimistic' about Massa's recovery, but cannot say anything for definite until the brain scans have been performed.
Until those tests have been completed, it is also too early to judge how long Massa's recovery will take - or if he will be back in Formula 1 action this season.
Barrichello visited the AEK hospital in Budapest last night to find out news on his fellow Brazilian's condition, while Massa's father and other family members are flying out to Budapest to be with him, having not travelled to the race.
F1 supremo Bernie Ecclestone also visited to the hospital for an update on how Massa was, and afterwards expressed his shock at the events.
"We thought we'd got through these problems," said Ecclestone. "I've spoken to Sid Watkins [F1 safety expert] and he's looking into it."