ABU DHABI, United Arab Emirates (AP) The biggest change for newly crowned Formula One champion Nico Rosberg this year was staying calm despite his often turbulent relationship with rival Lewis Hamilton.
Rosberg won his first F1 title on Sunday to end his Mercedes teammate's bid for a fourth title overall. Hamilton won the race itself but Rosberg's second place was enough for him to finish five points ahead in the standings.
The German driver focused on himself the whole season, not allowing the frustrations of his rivalry with Hamilton to unsettle him.
''For sure it's a key ingredient as to why I'm here now. It's the approach I've taken,'' Rosberg said. ''I've really learned to focus hard. It takes a lot of sacrifice to stay so focused for the whole year.''
When Hamilton sealed last year's title with three races to go at the United States GP in Austin, Texas, he made a dismissive gesture toward Rosberg.
The three podium finishers each get a cap: with 1st, 2nd, and 3rd written on them. Race winner Hamilton tossed Rosberg's second-place cap toward him with barely a glance in his direction, let alone consoling words.
Rosberg reacted by tossing it straight back at Hamilton even quicker than it had arrived.
Hamilton's gesture appeared to be one-upmanship, goading right at the precise moment when his teammate was utterly dejected.
''Austin was a horrible experience for me,'' Rosberg said.
But getting so irritated that day merely exposed his frustration to the watching world, while Hamilton smiled serenely.
Rosberg showed far more mental strength this year.
Even at pre-season testing in Spain, he seemed different. Less edgy, less verbose, and quietly determined to turn his fortunes around.
All season long he has repeated the mantra of taking it one race at a time.
The clich� from one of the more eloquent drivers became a force field, helping him to block everything else out and stopping him looking too far ahead or thinking too much about Hamilton.
Publicly, at least, he spoke about Hamilton like he would any other driver, rather than the rival haunting his title dreams.
There have been tensions this year.
They crashed on the final lap in a dramatic end to the Austrian GP in early July, when Hamilton was desperately trying to overtake Rosberg. It followed a similar incident on the first lap at the Spanish GP in mid-May - although both went out so neither gained points.
But after what happened in Austria, both were warned by Mercedes that they risked having team orders imposed on them.
Mercedes had seen this before in 2014, when their drivers feuded at the Monaco GP and the Belgian GP.
Tensions were still apparent heading into the final race of 2014 in Abu Dhabi. Before that year's title decider, Hamilton was asked if there was something he could do to ensure a clean race. He said there was not.
In a flash, Rosberg snapped at the British driver: ''Yes, Lewis can do something to keep it clean, which is drive cleanly himself.''
It was Rosberg once again rising to the bait.
But after this year's incidents, Rosberg reacted in a low-key manner, noticeably steering away from score-settling.
Even in the days before this race, Hamilton was stepping up the mind games, repeating that he thinks he has been the better driver this year and consistently bemoaning his bad luck with engine problems.
If Hamilton's intention was to dominate the pre-race news conferences before their latest title decider, then he won hands down.
But Rosberg was clearly not interested in engaging in a war of words and, while Hamilton hogged the limelight with his audacious statements, Rosberg sat next to him, cupping his chin on his hand, visibly detached as he looked away into the distance.
If Hamilton's intention was to undermine Rosberg's composure, then it failed.
Their rivalry goes back to when they were racing karts against each other as teenage friends and shared rooms together at races.
The two 31-year-old drivers are contrasting characters.
The jet-setting Hamilton has always loved to travel, often using his bright-red Bombardier Challenger private plane.
He has a taste for the high life, with high-profile friends in the music and fashion industry such as singer Rihanna, designer Stella McCartney and model Gigi Hadid.
In contrast, Rosberg, who has a young daughter with his childhood friend and wife, grows and eats his own vegetables.