Ben Spies claimed provisional pole ahead of round four of the World Superbike championship in Assen, Holland.

The American carried his form from the opening practice session into first qualifying to knock Jakub Smrz down to second and remain on course for a fourth straight pole.

Yamaha rider Spies clocked one minute 38.747seconds, 0.308secs ahead of his Czech rival, with Yukio Kagayama of Japan third quickest.

Spies, who has won three of the six races so far this season, goes into the weekend looking to cut the 40-point gap to Noriyuki Haga, who leads the standings on 135 points.

Ducati rider Haga could only manage 12th fastest in qualifying, having been sixth fastest in practice.

But he did win both races last time out in Valencia despite Spies starting from pole.

Spain's Carlos Checa qualified a provisional fourth and Italy's Michel Fabrizio fifth, with Regis Laconi, Max Neukirchner, Briton Jonathan Rea, Ryuichi Kiyonari and another British rider, Leon Haslam, making up the top 10.

Second qualifying will take place tomorrow morning before a free practice session and the afternoon superpole.