World ranking: 10th
Qualification: Third in 2015 pool
Best result: Pool stage
TAB odds: $151
Chances: While they have never moved past the World Cup pool stages, the 'Brave Blossoms' pulled off one of the greatest all-time upsets, when they toppled South Africa four years ago.
They're on home turf this time and probably need to beat Samoa and Scotland to advance - if they're ever going to do it, this is the time.
The Christchurch-born loose forward had the game of his life against South Africa in 2015.
Leitch was arguably the best player on the park, when the 'Brave Blossoms' shocked the sporting world with a 34-32 win.
Leitch has since had a decent stint at the Chiefs, before joining the Sunwolves for the last two Super Rugby campaigns.
This will mark Leitch's third World Cup and second as captain, after Eddie Jones handed the 30-year-old the armband in 2014.
Picked to lead Toyota Verblitz straight out of university by Jake White, Kazuki Himeno is a future leader of his country.
The young flanker, who has also played lock, is one of Japan’s main ball-carriers and always seems to get over the gain-line.
He's also a mean defender and the source creates plenty of turnovers.
Keita Inagaki, Yusuke Kizu, Koo Ji-won, Isileli Nakajima, Asaeli Ai Valu, Takuya Kitade, Atsushi Sakata, Shota Horie, Luke Thompson, Wimpie van der Walt, Uwe Helu, James Moore, Hendrik Tui, Yoshitaka Tokunaga, Michael Leitch (captain), Lappies Labuschagne, Kazuki Himeno, Amanaki Mafi
Kaito Shigeno, Fumiaki Tanaka, Yutaka Nagare, Yu Tamura, Rikiya Matsuda, Kenki Fukuoka, Ataata Moeakiola, Lomano Lemeki, William Tupou, Ryoto Nakamura, Timothy Lafaele, Kotaro Matsushima, Ryohei Yamanaka
Japan v Russia, Tokyo, 10:45pm
Japan v Ireland, Shizuoka Prefecture, 7:15pm (live updates)
Japan v Samoa, Toyota City, 11:30pm
Japan v Scotland, Yokohama City, 11:45pm (live updates)