Roberts takes provisional pole at Donington.

Despite still suffering the after-effects of his monster high-side at Assen, Kenny Roberts Jr found enough in reserve to land top spot in first qualifying for the British Grand Prix.

The American might still bear the scars of his brush with the Dutch tarmac, but was good for a three-tenth advantage over the rest of the GP500 field at Donington Park after the first hour-long session. Under bright sunshine, albeit accompanied by a breeze, Roberts casually extended his early advantage on his penultimate lap to give himself a handy gap going into tomorrow's deciding session.

Second place fell to the impressive Valentino Rossi, making his first appearance at Donington on a 500, but obviously drawing on the experience of winning at the circuit in both junior classes to fend off the opposition. The young Italian was in spectacular form through the Craner Curves, and looked set to take a mid-session pole before losing the edge towards the end of the lap. Nevertheless, second place gives him a good platform from which to chase his first GP500 victory come rain or shine tomorrow.

Rossi's Roman nemesis, Max Biaggi, was the one to lose out to the youngster's late surge, being bumped to third after showing his own hand early in the hour. The Yamaha rider did find an improvement towards the end, but it was good enough only for third.

Assen winner Alex Barros actually held second until the closing stages, but was beaten back by the improvements of his rivals. A spot on the front row was a bonus, however, given the fact that he languished well down the order in the opening half of the session.

Row two is shared, for the moment at least, by the quartet of Nobuatsu Aoki, Alex Criville, Tetsuya Harada and Norick Abe. The Suzuki rider put in another of his regulation solid showings to back up team leader Roberts, while Criville looked good for a front row spot before the rash of late improvements. The reigning world champion found time in his Honda, but it was not enough to return him to the front four, and he will be hoping for another dry session on Saturday.

Harada gave Aprillia something to cheer on a track where it half expects to challenge the V4s for the podium, but British team-mate Jeremy McWilliams tried a little too hard and high-sided coming out of the Old Hairpin and had to be helped from the side of the track by marshals. He was alert, however, and is expected to resume his pursuit of a top eight position tomorrow.

The two Red Bull Yamaha riders slipped down the order after holding good positions in free practice, while Italian GP winner Loris Capirossi could only manage 13th spot. This still marked an improvement over the free session, where the Pons rider was stone last, but Capirossi's hand injury is clearly giving him more concern than he would care to admit.

GP500 returnee Anthony Gobert could only manage 20th on his first real outing on the Modenas KR3, and trailed British privateers John McGuinness and Phil Giles, despite the latter also crashing out.

Earlier, Youichi Ui had landed provisional pole for the GP125 class, en route to what he hopes will be his fourth win of the year.

The diminutive Japanese propelled his Derbi to successive outright class records in pursuit of top spot, before eventually leaving the new mark at 1min 38.413secs on his very last lap of the session. This was good enough to give him a three-tenths advantage over nearest rival Noboru Ueda, who led a Honda completion on row one.

Ueda, a renowned lover of the Donington circuit, had earlier topped the free practice session from Givi team-mate - and team owner - Lucio Cecchinello, and the pair were again inseparable in the timed session. Seven-tenths may have divided the pair at the chequered flag, but Cecchinello had enough in hand to fend off the advance of reigning champion Emilio Alzamora.

Row two currently belongs to three Italians and a remarkable Czech, with Gino Borsoi and championship leader Roberto Locatelli heading the way. Behind them, however, are two of the stories of the season, with Mirko Giansanti making a premature return from injury to take seventh despite his broken wrist, and Jaroslav Hules wringing more and more from his Italjet to again land a top eight place.

Briton Leon Haslam clocked 24th best time on his return to a circuit he knows, and heads a home trio including wild cards Kenny Tibble and Stuart Easton. His position is at least expected among the experienced field, however, unlike that of Arnaud Vincent (18th), who continues to struggle with his Aprilia after a good start to the year.

Full times and details of the GP250 session will follow shortly....

Leading provisional qualifiers - GP500.

1. Kenny Roberts Jr Suzuki
2. Valentino Rossi Honda
3. Max Biaggi Yamaha
4. Alex Barros Honda
5. Nobuatsu Aoki Suzuki
6. Alex Criville Honda
7. Tetsuya Harada Aprilia
8. Norick Abe Yamaha

Leading provisional qualifiers - GP125.

1. Youichi Ui Derbi
2. Noboru Ueda Honda
3. Lucio Cecchinello Honda
4. Emilio Alzamora Honda
5. Gino Borsoi Aprilia
6. Roberto Locatelli Aprilia
7. Mirko Giansanti Honda
8. Jaroslav Hules Italjet