Great Britain have lost their five-match series against Argentina after a 3-2 defeat in the third Test. It was Argentina's third consecutive victory, and third time that Britain had let slip an early lead.
Britain led 2-0 for 15 minutes before allowing Argentina to take control of the game.
Dave Mathews and Mark Pearn scored for Britain before Carlos Retegui and Mario Almada grabbed penalty corners and Mario Almada clinched the win.
GB manager David Whittle said: "We started very well with great intensity in the first half and we certainly deserved the lead but we went off the boil a bit.
"They didn't perform as a team in the second half. Maybe that is because they are playing for their places [at the Olympics] and sometimes they didn't look for team goals but individual ones.
"At times we looked really positive but, at the end of the day, they have got to win the games."