Rodriguez takes advantage of Heidfeld penalty to win

Rodriguez hit the front after pole position winner and early leader Nick Heidfeld was penalised with a stop-go penalty for failing to slow sufficiently at the scene of an accident.

'I thought I could catch him anyway, to be honest,' said Rodriguez, 'because once I had settled into a rhythm and got my brakes up to temperature my car was just brilliant.

'I don't know that I could have passed him, of course, but I'm really happy with the way things have worked out. Now I've got the championship lead, I'm going to do my best to keep it.'

Heidfeld was bitterly disappointed to be given a penalty and he slipped to seventh as a result of his indiscretion.

'I slowed when I passed the incident,' he said. 'My next lap was much quicker, which I thought proved the point - but once these decisions are taken you can't do much about it.'

Frenchman Nicolas Minassian was on course for a career-best second place until a throttle failure forced him out with just five laps to go.

Jason Watt - desperate to finish after throwing away the lead here last season - thus inherited second and Max Wilson moved up to third after on-form Italian Oliver Martini crashed out on lap 40 of 50.

Oliver Gavin was best British driver, in fourth place. 'We made a change to the car on the grid,' he said, 'and with hindsight that was an error. The balance wasn't quite so good, but I'm delighted to score some points this early in the season.'

Gavin fought hard to hold off Stéphane Sarrazin, but although Sarrazin eventually found a way through he did so by leaping over the chicane kerbs.

The Frenchman was duly penalised and thus dropped out of contention. The top six was completed by Norberto Fontana - up from 17th on the grid - and Bruno Junqueira.

Portuguese driver Andre Couto failed to start the race after falling from a scooter on his way to dinner the previous evening. Though cut and bruised, he should be fit to return to the cockpit in the next race at Barcelona on May 29.

Race Results from Monaco