Argentina humiliated double defending Olympic champions Germany 5-2 to reach the men`s hockey final for the first time on Tuesday.
The South Americans pounced on a German team who only squeezed into the semi-finals by scoring three times in the last five minutes to beat New Zealand in the quarter-finals.
Defender Gonzalo Peillat hit a hat-trick of penalty corners with Joaquin Menini and Lucas Vila giving Argentina a 5-0 lead.
Menini`s 35th minute goal was the pick of the bunch when he escaped a defender and lifted the ball over the head of German goalkeeper Nicolas Jacobi.
Peillat`s triple took his total for the tournament to 10.
Argentina, ranked at seven in the world, have already surpassed their best previous Olympic performance of a fifth-place finish at the 1948 Games in London.
Four years ago, in London again, they were 10th.
In the final they will face the Netherlands, who were Olympic champions in 1996 and 2000 and silver medallists in 2012, or Belgium.
The European neighbours play their semi-final later Tuesday.