Motor Racing: Senna relies on the wet to challenge Williams: Hill primed for Spanish Grand Prix

PREDICTING Formula One races has become more about weather forecasting these days. The Williams-Renault team arrived here yesterday to pleasant sunshine, but by late afternoon it was raining and they fear the depression will stay all weekend. They are not merely alluding to meteorological conditions.

Yet again, it seems only rain can threaten Williams and their No 1 driver, Alain Prost, in Sunday's Spanish Grand Prix here, yet it offers their rivals, McLaren-Ford and Ayrton Senna, the encouragement they need. Much as McLaren have progressed and brilliant as Senna is, Williams and Prost have the power, and on dry tracks they are able to exploit that advantage.

The relatively silent player in all this is the other Williams driver, Damon Hill. While Prost and Senna have shared the wins from the first four races, Hill has had two second places and two offs, and accepts he has the responsibility of making a greater contribution to the championship. To achieve that he has to seriously challenge and occasionally beat Prost.

'I realise Formula One needs competition to make it a spectacle,' the Englishman said. 'No one wants to see a procession, no one wants formation driving, so it's up to me to be more aggressive and give Alain a real battle. Given a bit of luck, a win is on the cards. You think you've done enough, but I realise now that victory is never handed to you on a plate.

'I've got the best car, so really I should only have Alain to beat,' Hill added. 'There are always going to be people in the pit lane who feel they would be doing better, given my car. I'm gettting closer to Alain but, after his win at Imola, he'll be even harder to beat.

'It's a funny sport. Although we're in the same team, we're like two centre forwards going for the same ball. I've not been told to play second fiddle to Alain and if the opportunity to overtake him arrives I'll grab it.'

Mercedes will end its Formula One involvement after this season, and will concentrate on touring car racing. This year, the German motor company has been backing the Sauber grand prix team, which will now use Ilmor engines in 1994.