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England tuned up for next week's game against world champions New Zealand with a comfortable 31-12 victory over Argentina at Twickenham.
However, while England started brightly, their second-half performance gave reasons for concern.
With England's forwards providing a solid platform and quick ball, Joe Launchbury, Billy Twelvetrees and Chris Ashton scored first-half tries.
But England were poor after the restart until replacement Ben Morgan scored a late try as a capacity crowd was reduced to virtual silence at times.
The win means England are unbeaten at home in 2013, while Argentina have lost their last seven Tests following a winless Rugby Championship.
But New Zealand are sure to provide a far sterner examination than this disjointed Pumas outfit, who were being led by new head coach Daniel Hourcade for the first time following the resignation of Santiago Phelan.
Argentina were also without captain Juan Martin Fernandez Lobbe and Racing Metro full-back Juan Martin Hernandez, arguably their two best players.
Owen Farrell gave the home side an early lead with a straightforward penalty after Tom Wood, who was all over the pitch in the opening exchanges, forced an infringement.
But Nicolas Sanchez levelled from the tee almost immediately from the restart after Lee Dickson's attempted clearance was charged down and Courtney Lawes gave away a needless penalty.
But when Farrell refused a penalty opportunity and opted to kick for the corner instead it was a clear indication of England's try-scoring intentions.
And Wasps lock Launchbury duly obliged, going over from close range after a destructive rolling maul.
Farrell's Saracens team-mate Marcello Bosch hit back with a long-range penalty only for England to come surging back.
First Ben Foden went on a dart down the left wing before Ashton, whose England place is in jeopardy following some under-par performances of late, came crashing into the line off the right.
However, Ashton maybe should have done better shortly afterwards, opting to step inside instead of going for the corner and coming up just short of the line.
But with Argentina's defence in disarray, centre Twelvetrees, who also came in for some criticism for his performance against the Wallabies, burst over for a try, taking three or four defenders with him.
Ashton further increased the lead when he appeared on Farrell's right shoulder, after some dynamic work in the loose by Dylan Hartley, and dived over for his 18th England try and his first since February.
Having looked assured before the break, England looked far from it in the second half, which was characterised by slow recycling of the ball, poor decision-making and aimless kicking from both sides.
Sanchez reduced the deficit with two penalties before England head coach Stuart Lancaster, presumably confident the win was already in the bag, emptied the replacements' bench. But the changes failed to spark an England revival.
Having previously looked dynamic at the breakdown, England became too deliberate and the midfield was almost anonymous.
And while Lancaster will be satisfied with the victory, the sight of fans streaming for the exits five minutes before the final whistle told its own story.
Meanwhile, New Zealand, who went unbeaten during the Rugby Championship, will be confident of gaining revenge for their defeat at Twickenham last autumn.
England: Brown, Ashton, Tomkins, Twelvetrees, Foden, Farrell, Dickson, Marler, Hartley, Wilson, Launchbury, Lawes, Wood, Robshaw, B. Vunipola.
Replacements: Corbisiero (for Marler, 41), Care for Dickson (52), Parling for Lawes (56), Morgan for B. Vunipola (56), Flood for Twelvetrees (62), T Youngs (for Hartley, 63), Cole (for Wilson, 63), Goode for Brown (75).
Argentina: Gonzalez Amorosino, Agulla, Bosch, Fernandez, Imhoff, Sanchez, Cubelli, Ayerza, Guinazu, Bustos, Galarza, Albacete, Matera, Farias Cabello, Leguizamon.
Replacements: Cordero for Imhoff (31), Tiesi for Sanchez (64), Landajo for Cubelli (63), Orlandi for Bustos (66), Carizza for Galarza (55).
Not Used: Iglesias, Lobo, Macome.
Referee: Pascal Gauzere (France).