Fukuoka - Ireland skipper Rory Best is taking a philosophical approach to Saturday's critical clash with Samoa, keeping calm as Typhoon Hagibis wreaks havoc on the Rugby World Cup schedule.

Ireland must score a bonus point win (with four tries) to keep their fate in their own hands in a three-way battle for two quarter-final spots from the hotly contested Pool A.

Scotland and Japan, the two other contenders, will not know until hours before kick-off on Sunday whether their game will go ahead as the typhoon powers towards their Yokohama venue.

Ireland will definitely play their match in Fukuoka, several hundred kilometres southwest of Hagibis' projected path and this "probably makes it easier" for Ireland, according to Best.

"We go out, we play our game. You assume the (Scotland-Japan) game goes ahead on Sunday and, if it doesn't, you cross that bridge when you come to it."

Among the various scenarios to decide the pool, if Ireland don't score four tries, they could finish the pool phase with only one loss but still be on an early flight home.

Best said his green machine did not lack confidence, but needed a bit of polish after being too good for Scotland and Russia but suffering a shock loss to Japan.

"The bits we did well were very typical of us. The bits we didn't do well... we didn't follow through with some of the fundamentals that we do really well when we're on top of our game," he said.

"When you look at that, you take confidence you're in a good place, but you just need to execute better."

Like Pacific island neighbours Tonga and Fiji, Samoa are making an early exit but want to go out in style.

Coach Steve Jackson said his team will take inspiration from Tonga, who pushed France to the limit in their final game, and Fiji, who did the same against Wales.

"Ireland are in the top three teams in the world and we're just going there to throw everything at it," he said.

"What better opportunity to finish the World Cup? Knowing that we're on an airplane on Monday, going home, to have a scalp like that would be great."

Putting aside the Japan defeat, coach Joe Schmidt said it was "business as usual" for Ireland who will face South Africa in the quarter-finals if they win their pool or defending champions New Zealand if they are runners-up.

"We can't control what happens with the Japan-Scotland game, so on Saturday it's up to us to get our business done as best we can," he said.

"We've just got to make sure our game gets finished with the right result for us... Once you get to the ground and you know the immediacy of the match, it tends to be able to focus the mind."

Robbie Henshaw will get his first game in the World Cup after recovering from a hamstring injury with Schmidt naming close to his best side to face Samoa.

Only Peter O'Mahony, who is in the reserves, and Garry Ringrose, who is being rested after playing the first three games, are missing from the perceived top Ireland side.

Flyhalf Johnny Sexton combines with long-time partner Conor Murray at nine while in the forwards, the versatile Tadhg Beirne moves from lock to the back row.

The tight five is predictably Cian Healy, Best, Tadhg Furlong, James Ryan and Iain Henderson.

Teams:

Ireland

15 Jordan Larmour, 14 Keith Earls, 13 Robbie Henshaw, 12 Bundee Aki, 11 Jacob Stockdale, 10 Johnny Sexton, 9 Conor Murray, 8 CJ Stander, 7 Josh Van der Flier, 6 Tadhg Beirne, 5 James Ryan, 4 Iain Henderson, 3 Tadhg Furlong, 2 Rory Best (captain), 1 Cian Healy

Substitutes: 16 Niall Scannell, 17 Dave Kilcoyne, 18 Andrew Porter, 19 Jean Kleyn, 20 Peter O’Mahony, 21 Luke McGrath, 22 Joey Carbery, 22 Andrew Conway

Samoa

15 Tim Nanai-Williams, 14 Ah See Tuala, 13 Alapati Leiua, 12 Henry Taefu, 11 Ed Fidow, 10 Ulupano Seuteni, 9 Dwayne Polataivao, 8 Jack Lam (captain), 7 TJ Ioane, 6 Chris Vui, 5 Kane Le’aupepe, 4 Teofilo Paulo, 3 Michael Alaalatoa, 2 Seilala Lam, 1 Logovii Mulipola

Substitutes: 16 Ray Niuia, 17 Paul Alo-Emile, 18 Jordan Lay, 19 Piula Faasalele, 20 Josh Tyrell, 21 Pele Cowley, 22 Tusi Pisi, 22 Kieron Fonotia