The stark facts for Hamilton is that he must win his fourth race running tomorrow and rely on Rosberg to finish off the podium to become the first Brit to win for world titles.
The first glimpse of Nico Rosberg and Lewis Hamilton ahead of the Abu Dhabi Grand Prix left little doubt as to who is feeling the heat as they go head to head for the 2016 Formula One drivers' title. The Japanese manufacturer quit the sport at the end of 2008, leaving Button without a drive, but a consortium led by Ross Brawn took over the team and, in one of sport's most remarkable fairytales, Button claimed the world title the following season, Brawn winning the constructors' championship.
McLaren previously announced that highly-rated reserve driver Stoffel Vandoorne will replace Button as Fernando Alonso's partner in 2017.
"I can't do a long run like this", he said, after grumbling about a lack of engine power. However, it is worth noting that of the three practice sessions, FP1 and FP3 are the least representative as qualifying and the race take place later in the day at sunset.
After he won the world championship in 2014 and again a year ago, the team chose to break up Hamilton's successful crew.
"In Brazil. I was joking that I would still be taking things one race at a time".
"If he is labelled "the world champion" it doesn't necessarily mean that's the way it's labelled in my heart", said the 31-year-old, who was quickest in both Friday practise sessions, making gestures for inverted commas.
Button retains an option to race in 2018 if both parties agree, although at this stage that seems unlikely.
Both started their F1 careers when they were 20.
Born 19 January 1980, Jenson Button is one of an elite handful of drivers who have developed as true superstars of Formula 1 in the last decade.
Formula One rivals Lewis Hamilton and Nico Rosberg can't even shake hands.
Despite never managing to clinch the ultimate prize, Massa is held in the highest regard in the paddock, something that was demonstrated by the guard of honour to welcome him back to the pits after crashing out of the Brazilian Grand Prix two weeks ago.
Rosberg agreed: "We've had some hard moments but also some good ones and this year I think we've made progress so it's generally neutral but of course a hard environment".
"You get to Formula 1 with many dreams and hopefully you leave the sport with memories - some unbelievable memories, some life-changing, some good, some bad".
Rosberg comes to Abu Dhabi after having spent some days with his family and friends, and will not change the approach he has used all season, treating the finale of the 21-race season "like any other race".
"I want to win by as big a distance as possible and that has not entered my mind", he said.