Yamaha Factory Racing's championship leader Jorge Lorenzo may have a 33-point cushion heading into the final four races, but with Pedrosa on blistering form and his Repsol teammate Casey Stoner returning from injury, race wins and even second places could prove much tougher to come by.
Pedrosa will undoubtedly be looking for a repeat of last year when he beat Lorenzo in second and Stoner in third at the Japanese circuit. Yet whilst Lorenzo will no doubt be riding with the championship in mind, he has stated that his goal is to race to win. This will also be true for the returning Stoner, with the Australian having missed the last three races through an injury on his right ankle sustained in Indianapolis.
Lorenzo's teammate Ben Spies will be looking to find that extra bit of performance out of his Yamaha this time out, with the aim of holding off the Monster Yamaha Tech 3 duo of Andrea Dovizioso and Cal Crutchlow.
44 points may separate the Italian and the Brit in the table, but out on track their fairing-to-fairing action is proving popular with everyone, apart from team manager Hervé Poncharal presumably.
San Carlo Honda Gresini's Álvaro Bautista will be hoping to find a solution to his bike's set-up issues as he looks to once again take the fight to the satellite Yamaha's, while LCR Honda MotoGP's Stefan Bradl aims to bounce back from the error that saw him crash out of third in Aragón.
The Ducati Team had a weekend to forget last time out and will first and foremost hope to get through the Motegi round injury free after Nicky Hayden gave everyone a scare with his crash in Aragón.
Valentino Rossi, who last year crashed on the first lap in Japan, has stated that he's looking forward to the race, and that he believes the Ducati should be competitive, whilst Hayden has pronounced himself fully fit.
The Ducati satellite riders, Cardion AB Racing's Karel Abraham and Pramac Racing Team's Héctor Barberá both had very different weekend's at Aragón last time out, with the Czech rider aiming for a repeat top-ten performance, and Barberá hoping to get the better of the ARTs this time.
It will once again be the Power Electronics Aspar duo of Aleix Espargaró and Randy de Puniet who will be the ones to watch as the pair battle it out for CRT supremacy, now with extra motivation after having signed for the team for the 2013 season.
In addition, having qualified within 1.7 seconds of the top rider in Spain, the new class is edging ever closer to being competitive against the factory prototypes. The line up of NGM Mobile Forward Racing's Colin Edwards, Came IodaRacing Project's Danilo Petrucci, San Carlo's Michele Pirro, Paul Bird Motorsport's James Ellison and the Avintia Blusens' Yonny Hernandez remains the same. There will however be changes in the CRT line-up as former Moto2 rider Roberto Rolfo replaces Mattia Pasini in the Speed Master team aboard its ART machine, and Iván Silva returns for Avintia in place of David Salom. Yamaha will also field its test rider Katsuyuki Nakasuga.