Fernando Alonso has put Lewis Hamilton on his list of all-time greats, admitting to be pleased with the prospect of seeing the Brit equal the five world titles of Juan Manuel Fangio.
Rivals when they were both in competitive cars, Alonso and Hamilton also spent a year alongside each other, at McLaren in 2007.
The relationship between the two men turned sour however, enticing the Spaniard to leave the Woking-based outfit after just a single season.
But despite the acrimony, Alonso had witnessed his former opponent's achievements, and now ranks him accordingly among the sport's greatest drivers.
"Probably Michael, Fangio, [Ayrton] Senna, [Alain] Prost, Lewis. Probably these will be the top five," said Alonso when asked to cite his top F1 quintet.
"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 didn't project Hamilton's future success back in 2007, but he did know at the time that his team mate was someone special.
"Probably at that time it was difficult to imagine what the future could bring for Lewis and any of the guys on the grid, but definitely he showed the talent from day one, fighting for the championship in his rookie year, winning in 2008," he said.
"Probably at the time we all agreed that five or seven world championships will be possible.
"Then obviously he 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."
Gallery: The beautiful wives and girlfriends of F1 drivers
Keep up to date with all the F1 news via Facebook and Twitter
Lewis Hamilton was particularly happy with his opening day of running at the Las Vegas…
Red Bull fears that its prospects for this weekend's Las Vegas Grand Prix - which…
Ferrari and Mercedes have both modified their car’s floor element in Las Vegas to comply…
Lewis Hamilton put Mercedes on top of the timesheets for the second time in Las…
Full results from Free Practice 2 for the Las Vegas Grand Prix at Las Vegas,…
Charles Leclerc believes that Ferrari has a genuine “shot” at beating rival McLaren to Formula…