Those failing to proceed to the main qualifying sessions included both Osellas; Nicola Larini and Piercarlo Ghinzani close together in fifth and sixth.

The two Williams were fourth and fifth with Thierry Boutsen, in his home race, ahead of Riccardo Patrese, followed by Nigel Mansell in the second Ferrari.

Alessandro Nannini was seventh in the Benetton, over two seconds behind Mansell, and the top ten was completed by Stefano Modena in the Brabham, Maurício Gugelmin in the March and Derek Warwick in the Arrows.

Mansell managed to pass both Williams on the grass on the run to La Source hairpin to claim fourth position by the first corner.

René Arnoux then retired in the pit lane on lap 5 after a collision with the Lola of Philippe Alliot at La Source.

Behind him, Berger suffered his tenth consecutive retirement of the season when he spun out on lap 10, leaving Prost to fend off a charging Mansell who, in his efforts to pass the McLaren, made a number of unorthodox moves at the exit of La Source in an attempt to gain a better run at the McLaren through Eau Rouge and on to the long uphill straight.