SPA-FRANCORCHAMPS, BELGIUM, AUG. 28 -- Michael Schumacher, the apparent runaway winner of the Belgian Grand Prix today, was disqualified when race stewards found that a speed-limitation device on his car did not meet requirements.

The ruling gave the victory to Britain's Damon Hill, reopening the world championship points race only four hours after Schumacher seemed to have locked it up with his eighth victory in 11 races.

Race stewards ruled that a mandatory wood plank under his car, aimed at slowing down drivers, did not meet measurement requirements.

It was either too thin or too light, giving him an advantage over his competitors.

"Stewards of the Belgian Grand Prix have decided to inflict a penalty on Benetton Ford and driver Michael Schumacher of exclusion from the event," international FIA federation spokesman Tom Walkinshaw said.

The crude board was introduced into the high-technology sport halfway through the season in the wake of two racing fatalities. Brazilian Ayrton Senna and Austrian Roland Ratzenberger were killed at the San Marino Grand Prix in May.

The incident is the third this year to jeopardize Schumacher's success, which once seemed vulnerable only to the guardians of Formula One racing.

Schumacher, driving under an appeal of a two-race suspension for disregarding a black flag at the British Grand Prix, will learn the outcome of his appeal on Tuesday in Paris.

A defeat could cost him the points earned during the appeal, as well as resulting in a lengthened suspension.

His Benetton Ford team is under investigation for an alleged infraction in the refueling procedures at the German Grand Prix.

Now, instead of leading the world standings by 35 points over Hill, Schumacher has 76 points to Hill's 55.

And more sanctions could be coming against Schumacher.

If he misses the upcoming Italian and Portuguese grand prix races and Hill wins both, the margin could be cut to one point with three races to go.

The German was so far ahead in today's race that even a sloppy spin in the 18th lap failed to bring the competition within striking distance. He finished 13.663 seconds ahead of Hill.

The spin could have shaved some wood off the board, which is 30 centimeters wide, one centimeter thick and runs the length of the car.

The car is allowed to lose only one millimeter during the race.