Argentina's Mario Ledesma Arocena, bottom, and Georgia's Davit Zirakashvili react after the scrum collapses during their Rugby World Cup match at the Manawatu stadium in Palmerston North, on Sunday. ((Natacha Pisarenko/Associated Press))

Felipe Contepomi scored a try and kicked two penalties as Argentina overcame a shock halftime deficit to fend off a determined Georgia 25-7 at the Rugby World Cup on Sunday, setting up a quarterfinal against New Zealand.

Winger Juan Jose Imhoff scored Argentina's first try in the 32nd minute of a scrappy encounter, but flyhalf Lasha Khmaladze's converted effort just before halftime put the Georgians up 7-5 at the interval.

Contepomi landed two penalties and capped off a sweeping move with his team's second try as Argentina reeled off 20 unanswered second-half points.

"Georgia played really well, we couldn't find a way through. Fair play to Georgia, they played a very good game," Contepomi said. "We tried to improve our game [in the second half]."

The Pumas rounded off victory with a late converted try when Imhoff kicked the ball down the left and utility back Agustin Gosio chased it down.

Argentina finished second in pool B behind England.

"I'm very happy to have qualified, that was the goal," Argentina coach Santiago Phelan said through a translator. "But the team did not play well today, they were not organized."

The Scots needed Georgia to win and stop Argentina getting a bonus point to qualify ahead of the Pumas, who now face a daunting task against the All Blacks to reach a second straight semifinal.

"I think we have a lot to do over the next week, but we are thrilled to get through," Contepomi said. "We have to rest and then to analyze the All Blacks to see their weakest point, if they have any."

Georgia, coached by former Scotland international Richie Dixon, started in bullish style.

"I was very disappointed with the outcome of this game. I don't think we got as much out this game as we put into it," Dixon said. "I think we were very much in this game, and I think the scoreline, while I congratulate Argentina on winning, still flatters them."

Contepomi was cut down by a late tackle as he launched his team's first attack through midfield.

Moments later, he may still have been groggy as he missed his first penalty attempt out wide right. He failed to land any of his three kicks in the first half, but then went 3-for-3 in the second period.

Argentina gave away possession too easily, dropping the ball three times in the first 15 minutes.

Contepomi then clattered into fullback Martin Rodgriguez as they both went to collect a high kick, underlining how scrappy their play was becoming.

Rodriguez had to be alert moments later when he slid accross the grass to grab the ball as Khmaladze sprinted after his own kick after an Argentina attack broke down.

Georgia looked far more lively, snatching up loose balls and pressuring Argentina under high kicks at every opportunity at Arena Manawatu in Palmerston North, with hearty support for both sides making for a festive atmosphere.

The Pumas continued to falter, with one move breaking down when centre Marcelo Bosch spilled an easy pass, but with eight minutes remaining in the first half flanker Julio Farias Cabello's pass found Imhoff, and he shook off two tackles in a race to the left corner.

If that was meant to calm Argentina's nerves, it had little effect and Georgia took the lead a minute before the break.

Flanker Giorgi Chkhaidze gathered a high kick and burrowed forward with Argentina surprised by the pace of Georgia's midfield foray. Scrumhalf Irakli Abuseridze gave a quick feed to Khmaladze, who moved the ball to winger Alexander Todua as he created the overlap down the right.

Todua took Khmaladze's pass cleanly, then held off a tackle while placing a well-weighted diagonal kick into Khmaladze's path. He chased it down and held off a desperate tackle for a try.

"We played well the first half, the guys did fantastic work. Argentina is a very good team, very hard to play against," Zedginidze said. "For the second half, especially in the last minutes, we had a lack of experience."

Fullback Malkhaz Urjukashvili, having missed an earlier penalty, got the conversion from wide on the right.

Argentina looked brighter and started the second half with aggression and intent, camping on Georgia's line.

The pressure paid when Contepomi finally landed a kick to restore Argentina's lead, and added another soon after to make it 11-7 with 20 minutes remaining.

With Georgia now conceding ground and penalties, centre Marcelo Bosch tried his luck from 35 yards out on the left, but his penalty landed well short of the posts.

Contepomi put the game out of reach when Argentina stretched Georgia's defence with a succession of quick passes from right to left, and Contempomi shrugged off one tackle, stepped inside another and squirmed over for a converted try.

Imhoff showed great alertness to send his kick down the right touchline with enough weight on it for Gosio to reach.

Georgia won only one match, against Romania, but won over many fans during the tournament with its wholehearted approach.

"I'm very proud of the way the Georgians have fronted up at this tournament," Dixon said.