May 26 (GMM) Renault is still backing Nelson Piquet to up his game, but paddock rumblings suggest that the French team's patience will not last for ever.

Indeed, it was rumoured at the scene of the Monaco grand prix that team boss Flavio Briatore is giving the struggling 22-year-old Brazilian only until Silverstone in July - three more races - to take a substantial step closer to the pace and performance of lead driver Fernando Alonso.

Moreover, the Swiss publication Motorsport Aktuell reports that Alonso's scheduled running at the test following the Canadian grand prix has been scrapped so that Piquet, whose father won three world championships, can be in the car on all three days.

The loudest related rumour of all at Monaco, however, was that Briatore considers Super Aguri's laid-off race lineup of Anthony Davidson and Takuma Sato as genuine candidates for Piquet's seat if he cannot improve in the near future.

Briatore half-backed Piquet's unimpressive first outing at Monaco as a grand prix driver.

"Nelson's race was disappointing, but Monaco remains a difficult test for a driver and it is a very unusual circuit," he said.