Aug.15 (GMM) Nelson Piquet Jr must wait until the end of September to learn if he will be retained by Renault in 2009, the German magazine Auto Motor und Sport claims.

According to the report published on Friday, the French team recently decided against simply taking up an option on the Brazilian rookie's current contract.

Instead, Renault and the 23-year-old driver's management have agreed to extend the option deadline date from August to the end of September.

Former double world champion Fernando Alonso, Piquet's current teammate, has said he will only decide which team to race for next year in the autumn.

Auto Motor und Sport claims that, should Alonso switch camps, Renault's French-Swiss test driver Romain Grosjean is first in line to replace him.

If the Spaniard opts to stay at Renault in 2009, however, 22-year-old Grosjean reportedly may still make his grand prix debut next season, at Piquet's expense.