Lewis Hamilton has described Sebastian Vettel as an "aggressive" driver on the track but stopped short of labelling his rival "reckless", despite a string of collisions and spins that cost the Ferrari man his chance at the Formula 1 world drivers' championship in 2018.
Hamilton was crowned world champion for a fifth time last weekend in Mexico, besting Vettel for a second year on the bounce.
However, whereas in 2017 Hamilton had a clear advantage thanks to his car, it has not been the case this year.
Ferrari often delivered a package capable of dominance, only for Vettel to spill vital points in France, Germany, Italy, Japan and the United States as a result of errors at the wheel.
Spinning out of the lead at Hockenheim was particularly heart-breaking for Vettel, prolonging his wait to win at the track he grew up a short drive from.
Asked if Vettel was a stern competitor, Hamilton told Motor Sport Magazine: "Yeah, definitely. But he's not reckless.
"It's very borderline to be reckless, immature reckless or control reckless. The best, like Seb and Fernando [Alonso], it's not reckless. It's aggressive but fair. That's how I think he is."
Hitting top form in the second half of campaigns has become something of a Hamilton hallmark, but he says it is purely a natural progression and not a sign that he holds back early on in seasons.
"We didn't hold back, we were giving it everything," he said of 2018.
"It's just that you get that summer break, get the chance to look at the first half of the season, look at the strengths and look at the weaknesses and see if you can fill in the spots.
"There's bits and bobs from each race that can fill in the blanks from the other races and if you put that puzzle together and do that well, you should be able to have a stronger second half season."