Heavy defeats to Scotland and South Africa respectively have quelled early optimism in both camps, and made the quarterfinals a slightly more distant prospect. The Springboks' ability, or fortune, to emerge from their defeat to the Brave Blossoms with two bonus points has put them three points clear in second place in Pool B. However, while a top-two spot remains a possibility, victory is of the utmost importance to Samoa regardless as a win would all-but seal their automatic qualification for the 2019 Rugby World Cup, to be hosted by Japan. In short there is plenty to play for in Milton Keynes.

Team news

Samoa coach Stephen Betham has made five changes to the side that lost to the Springboks, in the process naming the most experienced side ever to represent the country at a World Cup. Johnny Leota, Tusi Pisi, Faifili Levave, Kane Thompson and Ole Avei are the players that come in, with Leota making his World Cup debut. Thompson, meanwhile, returns having served a two-match ban for striking Saia Fainga'a during his side's 27-24 defeat to Barbarians prior to the tournament.

Japan also go into the match with a line-up stacked full of experience, with coach Eddie Jones picking a XV with a staggering 615 Test caps between them. Jones has also made five changes for the clash in Milton Keynes, as Kensuke Hatakeyama, Hitoshi Ono, Ryu Koliniasi Holani, Kosei Ono and Akihito Yamada come in. The Brave Blossoms have also been handed a boost on the bench where Amanaki Lelei Mafi is fit to take his place, despite being carried off in Gloucester.

© Dan Mullan/Getty Images

Samoa: Tim Nanai-Williams, Ken Pisi, Paul Perez, Johnny Leota, Alesana Tuilagi, Tusi Pisi, Kahn Fotuali'i; Sakaria Taulafo, Ole Avei, Census Johnston, Teofilo Paulo, Kane Thompson, Ofisa Treviranus (captain), TJ Ioane, Faifili Levave

Replacements: Motu Matu'u, Viliamu Afatia, Anthony Perenise, Jack Lam, Vavae Tuilagi, Vavao Afemai, Mike Stanley, Rey Lee-Lo

Japan: Ayumu Goromaru, Akihito Yamada, Male Sau, Harumichi Tatekawa, Kotaro Matsushima, Kosei Ono, Fumiaki Tanaka; Keita Inagaki, Shota Horie, Kensuke Hatakeyama, Luke Thompson, Hitoshi Ono, Michael Leitch (captain), Michael Broadhurst, Ryu Koliniasi Holani

Replacements: Takeshi Kizu, Masataka Mikami, Hiroshi Yamashita, Justin Ives, Amanaki Lelei Mafi, Hendrik Tui, Atsushi Hiwasa, Karne Hesketh

Key head-to-head

Convincing Tim Nanai-Williams to switch allegiance from New Zealand always looked something of a coup and so it has proved. The fullback got his country's first try in their opening match against the USA. Even as his side subsequently slipped to a 46-6 defeat to South Africa, Nanai-Williams showed his class, gaining more yards with ball in hand than all but three players on either side. On Saturday, though, his opposite number will be Ayumu Goromaru -- arguably the player of the first week of the tournament. Goromaru is a different prospect to Nanai-Williams but his trusty boot will be integral to how Japan approach what is a must-win game for both sides.

Key stats

*Both coaches have picked their team's most experienced Rugby World Cup XV, although Japan's 615 caps dwarfs the 346 Samoa boast.

*Two of Japan's three wins over Samoa have come in the last five years, with their most recent win coming in May, 2014.

*Tusi Pisi -- who plays his club rugby in Japan -- needs just 17 points to overtake Earl Va'a (174) as Samoa's highest-scoring Test player. However, on his only previous appearance against the Brave Blossoms he failed to score a single point.

Odds

Japan may have beaten the Springboks already during this World Cup, but Unibet have made Samoa heavy favourites, offering a best price of 7/25 for a Pacific Island win. Japan are a much longer 14/5 but there might be some value in that. Alternatively, 4/5 for Manu Samoa to be the first team to 20 points, 43/20 if you think it will be Japan or 37/10 if you don't think either will hit that mark.

Weather

Saturday is set to be cloudy in Milton Keynes, with a temperature between 13 and 14 degrees celsius when the game kicks off at 2.30 p.m. The sun should appear before the end of the game, while the rain should hold off until Sunday meaning Samoa's backs should get plenty of opportunity to run the ball.

Prediction

Japan have had an extra three days to prepare for this clash, but it remains to be seen how much toll the second half against Scotland has taken on the Brave Blossoms. Samoa have still had a full week to bounce back from their own blow against South Africa, and have history on their side. Ahead of the tournament this match looked like a banker for the Samoans, but Japan have shown themselves to be dangerous and if the Pacific Islanders are to secure another defeat of the Brave Blossoms, then it will not be by many more than seven points.