Another title 'showdown' looms large
Japan has been no stranger to championship showdowns in the past, and while there are still five races to go in this year's fight, events this weekend in Suzuka - where Lewis Hamilton and Nico Rosberg duelled last year - could well prove decisive.
In slipping to 23 points behind Rosberg, Hamilton has no room for error. Anything but victory would therefore leave him extremely vulnerable. If Rosberg wins and Hamilton is second, for example, the Briton's deficit would widen to 28 points - just recoverable by winning all the remaining four races, assuming Rosberg is second in all four. In such a scenario, both men would be tied for points - with Hamilton only ahead on wins countback.
All the permutations of course assume that both men will be free of bad luck for the run-in - and recent races have proved the folly in ignoring the role of fortune in Grand Prix racing...
There is an additional element for the Hamilton camp to consider after his engine fire last weekend: he now has just two engines to get him through the last five races, which could disrupt future weekends.
"Right now, my concern is I've got these two engines and I want to make sure they can treat them with whatever they can to make sure they last," he says. "If that means not doing a session, I will not do a session. I'll do whatever it takes to see through a race.
“All I can do is keep my head down, and do the best job that I can and see what happens...”
Is Rosberg on a roll?
Champion's 'luck' is an intangible quality, but one that nevertheless exists - and there were heavy shades of it in the manner of Rosberg's comeback to third in Malaysia.
The German himself couldn't quite believe the reversal of his fortunes, which put him in the driving seat heading into Suzuka this weekend - the venue that kick-started his run of six consecutive pole positions at the end of last year's championship.
"My start was good, I was on the outside of Lewis and then I felt a massive hit on the rear which spun me round," he said of his incident at Turn 1 in Malaysia five days ago. "I was sure that was it, I was sure the car was broken.
"Of course I was happy with the comeback; to get all the way back on the podium, I definitely didn't think that was going to be possible.
"Points-wise it was a good day for me, even though not for the right reasons, because I want to get them on merit. I can understand Lewis's situation because I've been there as well and it's horrible when you deserve to win a race and the technology lets you down.
"I'm sure he's really, really gutted, that's very understandable.
"Now I just want to focus on doing the maximum in Suzuka, where hopefully Mercedes can clinch the world championship for constructors."
Vettel's remarkable Suzuka record under pressure
Since F1's return to Suzuka in 2009, the Japanese circuit has hosted seven Grands Prix. Vettel has finished on the podium in every single one.
That streak is in jeopardy this weekend however, and not just as a result of Red Bull's resurgence. The four-time world champion carries a three-place grid penalty into Sunday's race as a result of his first-corner collision with Rosberg in Sepang. On a circuit where overtaking is difficult, he and Ferrari therefore start the weekend on the back foot.
It compounds what has been a difficult period for the German. Vettel has just one podium in his last eight races - his worst run since his first full season in the sport back in 2008 with Toro Rosso. He has dropped to fifth in the standings, behind team mate Kimi Raikkonen and Red Bull's Daniel Ricciardo, the latter of whom is now 51 points up the road.
Ferrari meanwhile are still chasing a first win of the season, and have dropped to 46 points behind Red Bull in the fight for second in the constructors' championship. Can they fight back this weekend - and can Vettel lead the way, even with this grid demotion?
A big weekend for McLaren Honda - in more ways than one
The Japanese Grand Prix is obviously a hugely important race for Honda anyway, but there is extra riding on this year's race after confirmation that Fernando Alonso is set to compete with their latest power unit upgrades on his Mclaren.
The Spaniard trialled the new updates during practice in Malaysia, and after positive reviews of the data gained, Honda have given the green light to run the upgrades herein.
"There's pressure to perform at every race, so nothing changes in terms of our desire to get a result," McLaren say. "But there's no doubt that our victories at Suzuka in 1988 and '91, with Honda, were very special and it would be fantastic to get another good result on their home turf this weekend."
Button meanwhile is likely to wait until the United States to receive the same upgrades, in order to avoid the associated engine penalties at Honda's home race.
The Briton of course is a popular figure in Japan, which adds an extra dimension to what could prove to be his final Grand Prix in the country.
"The Japanese Grand Prix is always one of my highlights of the year," he says. "I love going back to Japan and the fans there make it incredibly special. They give us 110 percent support throughout the whole week, right from the minute we arrive in Tokyo, and as drivers we really feed off that enthusiasm.
"As it's another home race for us, we'll be very busy in the lead up to the weekend itself, and it's an important grand prix for the whole team, so I hope we can fight hard and get the best result we can to give something back to the enthusiastic fans."
WATCH: Your guide to the iconic Suzuka circuit
Ricciardo scents another opportunity to spring an upset
"The way I see it, if we both finished on the podium in Sepang, we obviously have a good chance here..."
There's no doubting the belief in Daniel Ricciardo's words heading into Suzuka. The Australian is on fire right now, delighted with the pace of Red Bull's development, and itching to push hard in Suzuka and see what happens.
Red Bull's Helmut Marko, after all, believes that the pressure his cars were applying was the reason why Lewis Hamilton's Mercedes engine broke. Don't expect the charging bulls to take their foot off the gas...
"Everything we put on the car, maybe our feedback is helping as well, but all the updates seem to be going in the right direction," Ricciardo adds. "Since I've been with Red Bull it's been the best year for that. A lot of things we've used or put on the car have worked.
"The level Max and I are maintaining is helping the team. We're certainly pushing each other. We're both driving at a pretty good level.
"Suzuka is a good circuit for us, one I personally enjoy a lot. I've always loved coming here, especially with the car we've got. It's a circuit where a chassis can really make a bit of a difference. It's a lot of fun. I think the package we have we can definitely fight for a podium."
Who has called tyres right?
Unusually the top five drivers in the championship have all made different tyre choices for this weekend. Pirelli's orange-marked hard tyre proved key to the race in Malaysia - and with the Italian tyre manufacturer providing the same three compounds (soft, medium and hard) this weekend, will that also be true for Suzuka?
Plenty of energy goes through tyres here after all - the long, fast corners maximise loads. Indeed the famous 130R contains the highest continuous g-force loading of the year. There are few longitudinal forces: instead Suzuka is all about lateral loads through corners. These factors tend to lead to high levels of wear and degradation, with more than one pit stop.
That could be good news for Red Bull, who have brought four sets of hards for both Ricciardo and Max Verstappen. Hamilton and Vettel meanwhile have three to pick from, while Rosberg and Raikkonen have two sets of the orange-banded tyre.
"For the first time we bring the soft tyre to Suzuka, which should provide a different aspect to the strategy, so we may have some tactical thinking right from qualifying on Saturday," says Pirelli motorsport director Paul Hembery.
"Whatever happens, we'll be seeing the hard tyre used during the race, as was the case in Malaysia, and also high wear and degradation: which always additionally provides varied strategic opportunities."
Last year Hamilton won with a two-stop strategy, starting on mediums, switching to mediums again on lap 16, then hards on lap 31. The best alternative strategy saw Nico Rosberg undercut key rivals to take second with a medium-hard-hard run.
All such plans could be disrupted by rain however - there are chances of showers or even thunderstorms on both Saturday and Sunday, which could turn the Grand Prix on its head.
The lights go out at 1500 hours local time (0500 GMT) on Sunday, with the race set to run over 307.471 kilometres, or 54 laps.