Valentino Rossi wasted no time in showing his intentions at Assen this morning, leading the first free practice session by a massive 0.69secs ahead of his nearest rival - Max Biaggi.

WSBK champ Colin Edwards put his superb Assen SBK record to good use to be a surprise third fastest, ahead of Catalunya winner Loris Capirossi, the Ducati rider 1.18secs slower than the Repsol pace setter.

Troy Bayliss also capitalised on his previous experience of the Dutch circuit to set the fifth fastest time, with Barros, Checa, Gibernau, Ukawa and Haga completed the top ten.

Kenny Roberts' replacement Yukio Kagayama was 17th fastest out of the 23 riders, two places and 0.4secs behind regular racer John Hopkins. Top Kawasaki was once again wild-card Alex Hofmann, in 16th.

First qualifying takes place this afternoon.

Thursday free practice:

1. Rossi
2. Biaggi
3. Edwards
4. Capirossi
5. Bayliss
6. Barros
7. Checa
8. Gibernau
9. Ukawa
10. Haga
11. Melandri
12. Jacque
13. Nakano
14. Hayden
15. Hopkins
16. Hofmann
17. Kagayama
18. Pitt
19. Tamada
20. McCoy
21. McWilliams
22. Aoki
23. Kiyonari