The 27-year-old has been one of the stars of the tournament, scoring four goals as Alejandro Sabella's side has claimed wins in all five of its games so far.
It faces the Netherlands in the last four Wednesday, and the Barcelona forward wants his side's campaign to keep going.
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"We've reached our first goal, to be among the final four," he told reporters. "Now we want more. We enjoyed what we experienced on Sunday but let's think about what's coming. We are prepared.
"We ran more than ever. We didn't create as much as other times, we didn't do as much as we did at other times. I played a different game and I had to run more than usual. When I came to the ball, I was a little tired but we are playing as a team."