Marco Simoncelli fell without harm from his Gilera after running wide over some kerbing, but his bike - hidden in a cloud of dust - then slid back across the track, where it was hit flat out by the unsighted Sekiguchi.
The Japanese was thrown into a full 360 degree flip by the impact, before landing heavily on his back. The session was immediately red flagged, but initial reports state that Sekiguchi is 'breathing and fully conscious'.
