Argentina and Scotland both admit this evening's pool B clash at the rugby world cup is probably the most important of their lives, with the winners likely to finish second and advance to the quarter-finals.
Six Nations champions England have already won all three of their games, including a tight 13-9 victory over Argentina in their opening game, and face the Scots next week in Auckland.
Argentina hooker Mario Ledesma says the Wellington clash is their biggest test to date
Ledesma's comments echoed those of Scotland winger Sean Lamont who says for the Scotland boys it's the be all and end all tonight
The other match with 'sudden-death' implications is the afternoon match up between Fiji and Samoa in pool D.
Both sides have lost one match so far and the losers will drop out of contention for second spot in their pool.
World champions South Africa lead the pool having won all three of their games.
Ireland are in Rotorua to play Russia late afternoon with a victory moving them back to the top of Pool C.