After seeing his side beat Samoa 17-13, Wales coach Warren Gatland said he wouldn't know what style of play the Pumas would adopt in Cardiff until after Twickenham.
Now he knows they are as strong as ever up front, have some exciting youngsters behind and will do their best to frustrate Ryan Jones and his team.
The wet and windy weather conditions dictated many of the tactics in a match that was eventually decided by a 70th minute try by left wing Matt Banahan. That came from a strong drive from No 8 James Haskell and some clever link work from his
back row colleague Lewis Moody.
Up until then it had been the boots of the respective goal kickers, England outside half Jonny Wilkinson and Argentinean centre Martin Rodriguez, that had steered the scoreboard to 9-9.
Pumas skipper Juan-Martin Fernandez Lobbe was unhappy at the result, but delighted with the way his side, featuring four new caps and playing their first game in five months, competed.
"For 70 minutes we kept our defensive line very well, but then we made one mistake. Now we know the level we need to play at," said Fernandez Lobbe.
"We have two very difficult games left and we need to go a step further. We mustn't make as many mistakes."
In drier conditions at the Millennium Stadium, the Pumas' front five are certainly going to cause Wales severe problems and it will be difficult for the home side to increase the tempo in their game unless they can find a way to keep Fernandez Lobbe and his expert foragers off the ball in the loose.
England were turned over seven times and spent the last five minutes defending desperately as the Pumas went for the try they needed to steal the draw.
England: Try: M Banahan; Con: J Wilkinson; Pens: J Wilkinson 2; DG: J Wilkinson.
Argentina: Pens: M Rodriguez 3.