Complex sentence: The race was a disaster for Heinz-Harald Frentzen-he stalled on the grid as the race was about to begin, forcing the start to be aborted and Frentzen to start from the back of the grid.
Split into simpler sentences: The race was a disaster for Heinz-Harald Frentzen. He stalled on the grid with the race about to begin, forcing the race start to be aborted and having him to start from the back of the grid.