Ben Youngs spared England's blushes as they came from six points behind to beat Argentina 13-9 in their opening World Cup Pool B match at the Otago Stadium.
England were trailing 9-3 when, after winger Chris Ashton was illegally upended, they kicked a penalty to touch. They won possession from the resulting line-out and replacement scrum-half Youngs, recently sidelined with a knee injury, went over for the only try of the match 13 minutes from time.
Jonny Wilkinson, who missed five of his eight goalkicks as he began his and England's quest to appear in a third successive World Cup final in uncertain fashion, added the conversion to make it 10-9 before landing a late penalty to extend his side's lead.
But there was still time for a last-gasp Pumas attack from their own line launched by replacement back Marcelo Bosch. A brilliant handling move ended with replacement Juan Jose Imhoff kicking ahead only to be seemingly tackled late by Manu Tuilagi. But referee Bryce Lawrence did not award a penalty and England hung on.
"I aged about 20 years," said England manager Martin Johnson. "We had to find a way to win and we did. "It's not a fantastic performance by any means, but it's a fantastic win," added England's 2003 World Cup-winning captain. "I always thought if we kept on going, we'd tire them out."
Scotland top Pool B, but were also unconvincing as they defeated Romania 34-24.
They had looked lively in the early stages and created two nice tries for Mike Blair and Joe Ansbro but Romania's forwards gradually took charge and after two penalties for Danut Dumbrava, prop Mihaita Lazar drove over for a try to keep his side in the game at only 18-11 down at the break.
Two penalties by replacement Ionut Dimofte and a try by Dan Carpo after a huge scrum then took Romania into a 24-21 lead with 12 minutes remaining with a massive shock on the cards.
Scotland, who have never failed to progress from the group stage of a World Cup, finally reacted with Danielli scoring twice in the last five minutes to spare his side's blushes and allow them to secure a bonus point for scoring four tries.
France began their challenge in Group A with a 47-21 win over Japan, but were made to work hard for the result.
The French dominated their lighter but more agile Asian opponents in the scrum and breakdown in the opening half but numerous mistakes crept in during the second period as Japan closed to within four points with 20 minutes to go.
New Zealand-born fly-half James Alridge was Japan's solitary scorer, running in two tries and kicking 11 points as the Asian side threatened to produce the greatest World Cup upset. However, Lionel Nallet, Pascal Pape and Morgan Parra powered over for a late tries to secure the win.
Fiji right winger Vereniki Goneva scored four tries, three in the first half, as the Pacific islanders held off Namibia 49-25 in Pool D.