Fernando Alonso believes Lewis Hamilton is among Formula 1's greatest ever drivers as he stands on the precipice of his fifth world championship.
Hamilton could wrap up this year's title at the Circuit of the Americas this week by scoring eight more points than rival Sebastian Vettel.
If successful, it would leave the Englishman equal with F1 legend Juan-Manuel Fangio, a driver many observers hail as the greatest driver to have ever competed in the sport.
Though stopping short of suggesting Hamilton was the best ever, Alonso believes Hamilton is in among F1's all-time greats.
“Probably Michael (Schumacher), Fangio, (Ayrton) Senna, (Alain) Prost, Lewis. Probably these will be the top five,” Alonso said when asked to name his top five F1 drivers of all time.
“It is difficult to compare different times and different ways to win those championships.
“Lewis winning five now and being the same as Fangio is a great achievement.
“If one had to do that in a generation I am happy it is Lewis as he showed talent and commitment when the car was dominating and won championships, and when the car was not good enough to win championships he put in some performances to show his talent. That is difficult to see in our days.”
Alonso admits he had no idea of the heights Hamilton would rise to when he made his debut in 2007, when they were both driving for McLaren.
That year he went toe-to-toe with Alonso and Ferrari's Kimi Raikkonen for the world championship, with the latter stealing it at the final race of the year in Brazil.
“Probably at that time it was difficult to imagine what the future could bring for Lewis and for any of the guys on the grid,” Alonso said.
“But definitely he had showed the talent from day one.
“Fighting for the championship in his rookie year, winning in 2008, probably at that time we all agreed that five or seven world championships would be possible.
“Then it was a little bit down due to the performance of the car for a couple of years.
“Switching to Mercedes, we were all thinking that was not positive as Mercedes was struggling in 2013, but it is up and down.
“I am happy for him as he showed talent from day one, he was able to win races where the car was able to win. It is impressive.”
A fifth title for Hamilton would leave him equal second on F1's honour with Fangio, with only Michael Schumacher's tally of seven championships ahead.
Hamilton currently has 71 grand prix wins and 80 pole positions to his name in 225 starts, while Schumacher amassed a record 91 wins and 68 poles (a record Hamilton has since beaten) in 308 starts.