After a slow start, in which he slipped to just 17th, Hayden's Repsol Honda team-mate Max Biaggi produced a solid charge from mid-race onwards and was eventually rewarded with seventh position, just over one-second behind Bayliss and six-seconds in front of former team-mate Makoto Tamada.
In contrast to Biaggi, Colin Edwards began well from his 15th on the grid, but his progress stalled in the latter stages and the American ended his Yamaha GP debut in ninth position, two-seconds ahead of the man whose M1 seat he took, Carlos Checa.
Kawasaki's Alex Hofmann, Fortuna Yamaha's Toni Elias, Ducati Marlboro's Loris Capirossi, Suzuki's John Hopkins and D'Antin Ducati's Roberto Rolfo completed the point scorers on a day when Suzuki's Kenny Roberts and Team Roberts rider Shane Byrne joined Hayden on the DNF list. Ruben Xaus did finish, but ran wide in the opening laps, required a pit stop and finished three laps down.
Despite the pre-race rumours, no rider is thought to have suffered from a lack of fuel today.
Full results to follow...