Ireland, Japan and Scotland are all in with a shout of reaching the quarter-finals by finishing in first or second place in Pool A. But how could things pan out with one match remaining?
As things stand, Japan are on 14 points, Ireland are second with 11 and Scotland lie third with ten. Ireland and Samoa meet on Saturday before the pivotal Scotland-Japan match on Sunday - assuming Typhoon Hagibis doesn't have other ideas. Here's a look at the various potential scenarios...
1. Japan beat Scotland
If Japan beat Scotland, the hosts will advance to the quarter-finals as Pool A winners with Ireland - provided they beat Samoa - also qualifying as runners-up.
2. Scotland beat Japan
If Scotland beat Japan and deny them a losing bonus point, Scotland would qualify with 14 points thanks to the head-to-head tie-breaker.
If Scotland beat Japan but the hosts secure a losing bonus point, Scotland would need a winning bonus point to ensure both teams finish on 15 points and the Scots advance on head-to-head.
If Japan secure two losing bonus points - by scoring four or more tries and losing by seven points or fewer - they would finish on 16 points and qualify as Pool A winners. Scotland would be knocked out if Ireland beat Samoa on Saturday.
In scenario two, a bonus-point win for Ireland against Samoa would see Joe Schmidt's side qualify as Pool A winners with 16 points IF Japan fail to pick up two losing bonus points. If Japan get two losing BP against Scotland, they will qualify as pool-winners and Ireland will join them in the knock-out stages if they simply beat Samoa - with a BP or without.
If Scotland beat Japan but both sides pick up a bonus point, Ireland would need to ensure a BP win over Samoa to avoid a scenario in which all three teams would be tied on 15 points - and Scotland would have an extremely good chance of ending up pool-winners thanks to points difference while Japan would also go through based on head-to-head results after beating Ireland. Scotland are on +71, Ireland on +52 and Japan on +46 but the runners-up berth is decided on head-to-head, not points.
3. Japan and Scotland draw
Perhaps unlikely, but if it ends all square between Scotland and Japan, the hosts will advance as pool-winners, even if Ireland secure a bonus-point win over Samoa. Japan, having beaten Ireland, would qualify in top spot and Scotland would be on the 'plane home.
4. Ireland lose to Samoa
If Ireland lose to Samoa and Japan beat Scotland and prevent them from picking up two losing bonus points, Japan and Ireland would qualify.
To sum up
The situation will be clearer after Ireland's match with Samoa but assuming Ireland record a bonus-point win over the Samoans, Scotland need to beat Japan with a bonus point and ensure the Brave Blossoms don't pick up any losing BPs to advance as runners-up.
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