Originally from the Gold Coast, near Brisbane, Australia, Doohan made his Grand Prix debut for Honda on a 500cc motorcycle in 1989, Doohan competed successfully throughout the early 1990s until a serious crash in 1992 nearly resulted in the amputation of one of his legs and left it permanently damaged. After an arduous recovery, Doohan returned to racing and through 1994 to 1998 was unstoppable in winning five consecutive 500cc world championships. Despite up to eight rivals on identical motorcycles (unlike Agostini, who very often had the advantage of a bike far superior to any of his rivals), Doohan's margin of superiority over them was such that in many races Doohan would build a comfortable lead and then ride well within his limits to cruise to victory.
One notable trait of Doohan's post-crash riding style was the use of a hand-operated rear brake, which he operated by a "nudge" bar on the left handlebar. Some commentators have argued that this technique offered Doohan an additional advantage in rear brake control, though there was nothing to stop other riders from trying it (and some did).
In 1999, Doohan had another accident, again breaking his leg and forcing his retirement (somewhat unluckily, as his accident rate was far lower than many competitors). He currently works as a roving adviser to Honda's Grand Prix race effort, notably advising Valentino Rossi.