SPIELBERG, Austria -- Japanese Formula One rookie Takuma Sato will remain in a hospital overnight after a 'miracle' escape from a major crash at the Austrian Grand Prix.

The 25-year-old's Jordan team said Sato had escaped unhurt from the dramatic accident that saw German Nick Heidfeld's out- of-control Sauber hurtle backwards across the run-off and into his car.

Chief medical delegate Professor Sid Watkins told team boss Eddie Jordan it was a miracle Sato was not seriously injured.

"Fingers crossed, everything seems to be fine, he's down there talking now and not even broken bones. It would appear there are no injuries at this time," Jordan said after leaving the pit wall to check on his driver.

The team said in a later bulletin that the 25-year-old would stay in Graz University hospital for observation.

His manager Andrew Gilbert-Scott said the driver had suffered some soft tissue damage to his right thigh but had been able to sit up and talk.

Heidfeld, unscathed but in shock after the accident, skidded ahead of a corner on lap 27 and hit Sato's car just as it was being lapped by the Williams of Colombian Juan Pablo Montoya.

"I saw a cloud of tire smoke as (Alex) Yoong braked really hard and early ahead of us and maybe I pressed the pedal too hard as a result while the brakes were still cool," said Heidfeld.

"The next thing I knew I was going backwards down the grass. I'm just thankful that Takuma is okay."

A medical team soon arrived and the Japanese rookie, who was briefly seen waving from his wrecked car, was eventually lifted out of the vehicle.

Jordan said the operation had taken some time because the rear of the Sauber had penetrated the side of the Jordan below Sato's right knee, making it difficult for him to move.

"The decision to keep Takuma in the hospital overnight is precautionary in order to check for any after effects of such a serious accident," said Jordan.

"The team does not know the full extent of the bruising or other injuries, nor how long it will take before Takuma is able to drive again."