Montoya puts Williams on top in Imola practice

Colombian Juan Pablo Montoya fired up his challenge to Ferrari's Michael Schumacher with the fastest lap in Saturday's opening free practice for the San Marino Grand Prix.

Montoya led a Williams one-two on a clear and bright morning at Imola after a steady downpour dampened his team's performance on Friday.

The Colombian, who has clashed with four times world champion Schumacher on the first lap of the last two races, lapped in a comparatively sedate one minute 29.718 seconds on a track still slippery from overnight rain.

Team mate Ralf Schumacher, Michael's younger brother and winner here last year, was a close second in 1:29.799, ahead of McLaren's David Coulthard.

Michael Schumacher, the championship leader and fastest on Friday when Ferrari led the times before their loyal fans at their home circuit, was fourth and 0.978 slower than Montoya.

His Brazilian team mate Rubens Barrichello spun and was ninth fastest with just nine laps completed.

Spaniard Pedro de la Rosa failed to record a competitive lap in the Jaguar after spinning off into the gravel trap with just three slow laps under his belt.