LONDON (AP) -- Two more teams could secure quarterfinal berths in the Rugby World Cup on Sunday: Ireland, which has done it five times, and Tonga, which has never qualified for the last eight.
Ireland has the relatively easier path, through Italy at the Olympic Stadium.
The Six Nations champion has been impressive in its two big Pool D wins over Canada and Romania, with fan support that has even taken aback the Irish.
Meanwhile, Italy has been two-faced. There was the Italy which overcame a malfunctioning scrum to give France a scrare, then the Italy which barely put away Canada. Italy could yet show another face with the return of talismanic captain and No. 8 Sergio Parisse.
But he hasn't played since he was injured on Sept. 5 in the narrow warm-up loss to Wales, and needed to have a hematoma in his left calf drained. He didn't join the squad for his fourth World Cup until Tuesday.
"He fought hard to be back," Italy coach Jacques Brunel says. "He wants to have a good World Cup. It is important for him, and important for us.
"He probably won't last the (entire) match, and that is why we have the need for two backrow replacements."
With Parisse underdone, Italy's hopes of staying in quarterfinal contention have been undermined by losing almost 200 caps in front-row experience: Stand-in skipper Leonardo Ghiraldini has a thigh injury, and Martin Castrogiovanni has a sciatic nerve problem.
The Italians describe this match as their "final," as do the Tongans of their Pool C match with Argentina in Leicester.
To make the quarterfinals for the first time, Tonga must win and not allow the Pumas any bonus points.
Below the All Blacks, the pool has been a dogfight: Argentina beat Georgia, which beat Tonga. The Pumas and Lelos have an advantage of finishing against Namibia, while Tonga has to play New Zealand. So the Tongans, fielding the oldest World Cup team ever with an average age of 31, have to do it now or likely wait four more years for their next chance.
"If we win, with a bonus point, it could take us somewhere we have never been before. We could make history here," captain Nili Latu said. "It's an exciting time for us, rather than a pressure time."
Here's a look at Sunday's games:
ARGENTINA vs TONGA (0-0 overall, 0-0 in RWC), Leicester, 1330 GMT
Because they are playing the Pumas, center Siale Piutau says Tonga are taking a wolfpack approach. "We are dying to get out on the field and get our howling on," he says.
But Tonga has to play smart. Georgia didn't last week against Argentina, which led only 14-9 into the second half when Lelos captain Mamuka Gorgodze was sin-binned. When he came back 10 minutes later, Argentina led 35-9.
Tonga coach Mana Otai says the Pumas have an edge in mental toughness from being exposed to the All Blacks, Springboks, and Wallabies in the last four Rugby Championship tournaments.
"They are fortunate enough to be competing with the best, year-in, year-out, and you only get better by being exposed to that, making adjustments, and having another opportunity to deliver," Otai says. "We don't have that opportunity until a World Cup, every four years."
He noted "hard times either grind you down or sharpen you up."
Tonga starts only five days after beating Namibia.
Argentina will have had nine days off. But it is without tighthead Nahuel Tatez Chaparro and utility back Juan Manuel Hernandez, who have hamstring strains. Rising star prop Ramiro Herrera, off the bench in the last two games, comes in and the Pumas are starting a new midfield of Matias Moroni, making his Cup debut, and Jeronimo de la Fuente.
They have an understanding, though, in eight games together this year in low-key internationals.
IRELAND vs ITALY (20-4 overall, 1-0 in RWC), Olympic Stadium, 1545 GMT
Ireland isn't risking center Jared Payne (bruised foot) and fullback Rob Kearney (leg muscle strain) and don't need them. Not with the form Keith Earls and Simon Zebo are in. Zebo was all flair against Romania at Wembley last weekend, and Earls was an easy man of the match.
"(Keith is) electric at the moment in training and on the pitch," returning flyhalf Jonathan Sexton said. "It's a case of get the ball in his hands and let him off."
With the chance to make the quarterfinals, Ireland has picked its strongest available side; 11 changes from the Romania win. The return of the likes of captain Paul O'Connell, Mike Ross, Sean O'Brien, Sexton, and Robbie Henshaw finally, has the side reeking of class and menace.
And with plenty of in-form backs, coach Joe Schmidt could satisfyingly say, "It makes for a fairly attack-minded group."