Sebastian Vettel rated Lewis Hamilton among Formula One's greats on Friday ahead of the Briton's attempt to win his sixth world championship at this weekend's United States Grand Prix.
Hamilton is set to confirm his place in F1 history in Texas on Sunday as he needs just four points to ensure that he retains his crown, a feat that would lift him to second in the sport's list of all-time greats behind seven-time champion Michael Schumacher.
Four-time world champion Vettel said that only Schumacher should be ranked beyond Hamilton, despite claims that he has benefitted from driving for serial champions Mercedes.
"How can we think differently? For me it is very clear. He absolutely is one of the best," he said.
"He has been here a long time and is one of the most successful drivers. After Michael, it is right to have his name there.
"Lewis is undoubtedly a great professional who stood out among all the drivers of his generation."
As his family flew in to witness his expected sixth world title coronation, Hamilton was boosted by the early return of a key man in his racing team on a chilly Friday morning in Texas -- his regular Mercedes race engineer Peter 'Bono' Bonnington.
Bonnington was absent last weekend in Mexico and had been expected to miss the American event after a personal medical procedure, but re-appeared in Hamilton's garage for Friday's opening free practice session.
The bespectacled racing boffin has engineered Hamilton to four of his previous five titles and, if the Briton is successful on Sunday, will have done the job for five titles in six years with Mercedes.
Hamilton, a victor on five of his seven visits to the Circuit of the Americas in Austin, will turn 35 in January, but has insisted he has no thoughts of retiring yet and believes he can continue to improve.
"I don't think I have hit my peak yet, and that is comforting. I plan to get stronger ... I never thought I would have five titles and I am continuing to create dreams that I didn't think I would ever have," he said.
"If I can get it, a sixth title will be unreal, but I am going to race for more years to come and I want to win every year. Believe me. I will push more than ever."
Having won 10 races this year, Hamilton is unchallenged as the master of his race craft, but is quick to point out that it has been a very challenging year in which Bonnington and the rest have played a full part.
"People underestimate how hard it has been. It has been a challenging year," he said.
"We often forget how many wins we had because it was so hard, but the numbers give a good feeling. Hard work pays off."