Fernando Alonso led the way in the final practice session for the Monaco Grand Prix, which was punctuated by two crashes that brought out red flags and limited running.

10222 - Fernendo Alonso fastest as accidents limit running

Alonso's fastest lap was set on the super-soft tyres and is the best of the weekend so far at 1:14.433. Jenson Button was second fastest but over 0.5 seconds adrift, ahead of the second Ferrari of Felipe Massa in third.

However, the second red flag, brought out after Tonio Liuzzi deposited his HRT in the barriers at turn one, meant that many of the front runners did not set a representative time on the option tyres.

Red Bull in particular focused on longer runs on the prime tyre for most of the session and did not get a clean fast lap on the super-softs. But judging by Sebastian Vettel's pace at certain points of the session, the championship leaders should still be the team to beat heading into the qualifying hour.

The first red flag came 20 minutes into the session when Nico Rosberg had a nasty accident under braking for the Nouvelle Chicane. His car came out of the tunnel dragging its undercarriage along the bumpy Monaco surface and then the rear snapped violently, pitching the nose of the car into the outside barrier.

Rosberg became a passenger as his car was launched over the speed bumps at the Nouvelle Chicane and was lucky to avoid the barrier separating the track and the escape road. His Mercedes came to a halt on the circuit and he walked away unharmed, but whether his team will be able to repair the car in time for qualifying is not yet clear.

Liuzzi's accident was less dramatic, although the repair job looked just as big. The car was unsettled heading through Sainte Devote and then swiped the barriers on the exit, making a mess of both the front and rear suspension on the left-hand side of the car. It was Liuzzi's second shunt of the weekend after he made an error into the Nouvelle Chicane on Friday.

The session restarted with less than two minutes on the clock and most drivers went out in order to complete a practice start on the grid after the chequered flag and no serious times were set.