The Mercedes duo's friendship and rivalry dates back to their boyhood days in the junior categories, but it could be tested to the limit in 2014 as the Brackley team looks set to dominate the 2014 title battle.
And the strain could already be showing.
"Nico often spends much more time with the engineers than I do," Briton Hamilton is quoted by the German newspaper Bild, "but we come to the same findings in the end."
Hamilton bristled at the suggestion Rosberg has a better chance of taming the highly-complex 2014 rules due to his more "technical" approach to racing.
"It's a strange perception that one driver (Rosberg) is massively technical and another is not," the 2008 world champion said.
"I didn't win the championship in 2008 from sheer luck."
German Rosberg insisted the comments, particularly the ones about wasting time with engineers, will not affect their relationship.
"It's no big deal for me," he said, "as two different approaches is a good thing."
However, it has emerged that even though the pair both live in Monaco, Hamilton has not been invited to Rosberg's forthcoming wedding.
"I don't mind," Hamilton said. "I try to avoid weddings anyway."
Meanwhile, members of the British media have criticised Hamilton for making "strange", "bizarre" and "insensitive" comments about the gravely injured Michael Schumacher.
Referring to the F1 legend's 11-week coma after a skiing fall, the 2008 world champion said in Melbourne: "I feel like all things happen for a reason.
"I think this is an experience that will really show his character and depth even more so than any other experiences he's had."