MERCEDES LOSING THEIR DRIVE?
Mercedes have become so dominant on track that one off-weekend in Singapore took the whole paddock by surprise.
Whether that was down to the freak loss of a small metal clamp, which ended Lewis Hamilton's race, or based on something more serious is open to question.
While Hamilton has voiced concerns, the Suzuka circuit plays to Mercedes' strengths much more than Singapore's street circuit, where Ferrari's Sebastian Vettel dominated last week.
BUTTON PUSHING OFF?
McLaren's Jenson Button is widely reported to be about to announce his retirement in Japan, the home country of his wife Jessica Michibata, and Honda, supplier of his team's engines.
The 2009 world champion has been in contract renewal negotiations with his long-time employers, who have struggled this season and currently lie ninth in the 10-team constructors' standings.
Trackside gossip suggests a possible future on TV for the popular Briton, who has promised to walk away from Formula One if he cannot remain at McLaren.
Engine supplier Renault's impending divorce from long-time partner Red Bull will be in focus, as will the French company's bid to buy Lotus and set up as a works team.
Meanwhile, Red Bull are now jockeying to team up with a new engine maker, with Ferrari considered the best - and perhaps, only - option.
One year on from Jules Bianchi's crash, commemorations will be in evidence at a sombre edition of the Japanese Grand Prix.
Manor, the Frenchman's former team, have promised to mark the event privately. But they expect an outpouring of emotion from fellow drivers and fans for the 25-year-old, who died from his injuries in July.
Japanese organisers will be keen to avoid a repeat of an incident in Singapore, where a fan wandered onto the track mid-race and crossed right in front of the startled race leader Sebastian Vettel.
A 27-year-old British man has been arrested and charged over the track incursion, a rare and extremely dangerous event in F1.