Saturday 12 May at 08:35 : May 12 (GMM) Romain Grosjean is a potential grand prix winner.

That is the claim of the Frenchman's first F1 teammate Fernando Alonso, who shared the Renault team with Grosjean in 2009.

The Enstone based team, however, was imploding amid the crashgate scandal, and Grosjean struggled to perform after being drafted in to replace the sacked Nelson Piquet.

He lost the drive at the end of the season and then found himself in the odd situation of farewelling his girlfriend, the French F1 presenter Marion Jolles, as she departed for a grand prix.

"She was there and I was home," Grosjean is quoted as saying in Barcelona by the Gulf Daily News. "Honestly, I thought it was over and I would never come back to formula one."

But, now as the new reigning GP2 champion, he is back in 2012 at the wheel of Lotus' black and gold E20 -- a car tipped by many as the favourite for victory this weekend.

Many naturally tip Grosjean's famous teammate Kimi Raikkonen as the most likely winner, but Spaniard Alonso rates the Swiss-born 26-year-old as well.

"When his car was not so good he was criticised a lot," Alonso told RMC Sport, "but when he has a good car he does very good results.

"He has won GP2 and has a fantastic career. He has talent and I'm happy he went onto the podium (in Bahrain).

"He can win a grand prix," the Ferrari driver professed.