Manuel Poggiali claimed his first ever World Championship with a measured ride to fifth place in tricky damp conditions in today's Rio Grand Prix.

The race was won by his sole championship rival Youichi Ui, but only after a thrilling last corner duel with Simone Sanna as the two finished over 27secs ahead of the final podium finisher Arnauld Vincent.

Youichi Ui must have been thinking about what might have been after setting a new pole record for the 125cc class yesterday as title rival Poggiali crashed out. The Japanese rider is without doubt the man of the moment in the eighth litre category - but his charge has surely come too late - Poggiali needed only to score more than three points today to win the title.

Other than the two championship contenders, Andrea Ballerini stood out from the crowd by qualifying second in what is only his second GP of the year, to outpace Telefonica teammates Pedrosa and Elias, third and fourth respectively.

However, any thoughts that Poggiali would simply need to cruise around the Nelson Piquet circuit to record a thirteenth placed finish - and with it his first World Championship, were thrown in doubt when rain fell this morning, with the track still wet (but drying) as the 500's completed their warm-up just prior to the 125 GP.

Poggiali's points lead was large, indeed Ui had to win today's race to have any chance of the title, but the San Marian would need to be careful in the unpredictably slippy conditions.

So, it was a particularly tense 125 grid that waited for the red lights to disappear for the final Grand Prix of 2001, and when the field were eventually released it was Ui who lead the field tentatively into the still damp turn one, with Poggiali having worked his way up to fourth after nearly colliding with Cecchinello off the start line.

Along the long back straight and Cecchinello slipstreamed his way up to second, before Ballerini retook the position towards the end of the first of twenty one laps.

Turning heads in the early stages was Stefano Perugini, the Italjet rider having stormed towards the front from a fourth row start, and by lap three the Italian was into second - and chasing race leader Ui.

Behind the #7 machine was Poggiali, while Cecchinello and Pedrosa, Vincent and Elias battled for fourth.

Lap three and Cecchinello lost control of his MS Aprilia in the tricky conditions as the Italian veteran was kicked off his machine on the exit of a right hander - scaring nearest pursuer Poggiali in the process.

Back up front and Perugini was putting up a sterling effort to hound Ui for the lead of the Rio GP, as the pair held a 4secs advantage over the cut throat battle for third headed by Pedrosa.

Having avoided Cecchinello's earlier exit, Poggiali nearly through the championship away himself when he was lucky to hold onto his Gilera after a big 'moment' - leaving him ninth and at the tail of the chasing pack.

Perugini's fight came to an end on lap six when he had a spectacular high-side form his #7 machine while trying to stay in touch with Ui. The experienced Italian was thrown high in the air, landing on his feet before sliding into the gravel trap next to his sparking Italjet.

It soon became apparent that the conditions were worsening as firstly Rodriguez, then Ballerini, fell from their machines and slid into the Rio countryside, while back up front Sanna had found an advantage over everyone else on track in the misty conditions as he began to gain time hand-over-fist on leader Ui, suggesting that the San Marian may have gambled on a 'cut slick' or the like.

Lap 9 and Poggiali was now in sixth and leading a five rider pack, with Bridgestone shod Masao Azuma looking confident - and soon taking sixth from the Gilera rider, while at the sharp end Ui had pegged the gap to Sanna to 2secs.

So, by lap 10 the order was: Ui from Sanna, Vincent, Pedrosa, Smrz, Azuma, Olive, Poggiali, Elias, de Angelis and Scalvini, with the San Marian soon slipping further back to ninth two laps later.

Meanwhile, slipping out of the race altogether was young Daniel Pedrosa; the 16 year old had out shone teammate Elias all weekend before sliding out of fourth on lap 13 in a premature end to his season.

Six to go and Sanna was still pressing as hard as possible, even taking 0.8secs out of the Japanese in just one lap to trim the deficit to 0.6secs, while Poggiali had now settled comfortably into seventh with a 1sec buffer between Elias and de Angelis.

As the race wound to a close, Sanna really wound the pressure on and with just 1 and 1 half laps to go he smoothly pulled inside Ui, with the Japanese rider retaliating just two corners later.

Onto the last lap and Sanna was all over the back of the Derbi, but was unable to capitalise on a slipstream along the back straight. Sanna's next chance came at the final turn as he did a do-or-die effort up the inside - but Ui toughed it out around the outside and got the drive to the finish to win his sixth GP of the year by 0.112secs, with Vincent seizing third after crossing the line 27secs later.

Behind the epic battle for victory, Poggiali crossed the line in fifth to claim his - and Gilera's - first ever World Championship, to the 18 year olds obvious delight as he waved enthusiastically to the Brazilian crowd and put on the obligatory "2001 world champion T-shirt." Poggi then returned to the pit lane where the celebrations continued with his Gilera squad.

UI, the bridesmaid once again, was gracious as ever in defeat - ever wearing a T-shirt saying "2001 runner-up" on the podium as a light hearted joke after finishing second in the World Championship for the second year running.

Full results to follow...

1. Ui
2. Sanna +0.112secs
3. Vincent +27.647secs
4. Elias +32.325secs
5. Poggiali +37.646secs
6. de Angelis +42.052secs
7. Azuma +42.563secs
8. Smrz +42.642secs