da Matta critical after deer smash.

Cristiano da Matta is in intensive care at Theda Clark Memorial Hospital in Wisconsin after being involved in an accident with a deer while at the wheel of his RuSport Lola.

The former Champ Car World Series titlewinner was testing at Road America prior to September's race when he collided with a deer that had wandered onto the track. Although he was quickly airlifted to Theda Clark, his condition remains serious after emergency surgery upon arrival.

"After arriving at Theda Clark Medical Centre, a head CT scan showed Cristiano had suffered a subdural haematoma," Champ Car director of medical affairs Dr Chris Pinderski reported, "He was urgently taken to the operating room for surgical removal of the haematoma and is now being observed in the intensive care unit."

Despite the shocking diagnosis, head injuries of this sort are not uncommon in race drivers involved in collisions, and many make a full enough recovery to resume racing.

IRL star Scott Sharp suffered a subdural haematoma - basically a clotting of blood below the brain lining - after hitting the wall at Indianapolis, but was saved from more serious injury by a combination of the recently installed SAFER barrier and swift medical intervention. Christian Fittipaldi incurred similar injuries in a Champ Car testing crash at Gateway in 1999, but was back behind the wheel five events later, while F1 driver Karl Wendlinger emerged from a coma to race again after his Monaco shunt in 1994.

The complication with brain injuries is that they rarely present exactly the same symptoms in consecutive patients, but most report similar side-effects and, with subdural haematoma, often claim to feel fine one moment, before succumbing to unsteadiness, double vision and bad headaches, symptoms that can endure for some time.

Should da Matta recover to the point where he considers returning to the cockpit, racing - and particularly US racing - now has a standardised test, based on visual reaction and short-term memory recall, to determine the true state of his health with regard to driving.

RuSPORT confirmed that da Matta's team-mate Justin Wilson would not participate in the final day of the open test on Friday, while it waits for updates on the Brazilian's condition. Ironically, the incident occured just days after da Matta's best result of the season, taking second place in San Jose following his recent move to RuSport from Dale Coyne Racing.