Opinions are split over whether Fernando Alonso should return to Formula 1 with Renault next year.
The Spaniard's friend and former rival Mark Webber thinks Alonso is "not at his peak anymore", while his first boss Giancarlo Minardi says Renault is not the right destination for the two-time champion.
"He has no chance to be in a top team, so if he returns it could only be in a mediocre car," Minardi is quoted by racingnews365.
But former Renault engineer Isaac Prada, who worked alongside the now 38-year-old at the French works team 15 years ago, encourages Alonso to return.
"Fernando is without a doubt the number one candidate for the place at Renault," he told La Voz de Asturias.
"There is the emotional factor but also the fact that he has won titles there. If he sees an opportunity that has potential then he will agree.
"Renault is a team with an excellent budget and serious intensions, and Alonso is able to go three tenths faster than the others. Don't forget that he fought for the title when he didn't have a car capable of it," Prada added.