Acasuso won the all-Argentine duel over the seventh seed to earn a third round match against Radek Stepanek of the Czech Republic, who edged out British number one Tim Henman 6-4, 1-6, 6-3.
Fourth seed Guillermo Coria stayed alive with a 6-3, 6-4 win over Christophe Rochus and will meet Chile's Fernando Gonzalez.
Top seed and world number two Rafael Nadal confirmed he will be fit to play a second-round match against Romania's Victor Hanescu later after a scan showed he was recovering from the tendinitis problems in his knees.
Argentina's Coria, who has reached two Masters Series finals this year before losing both to Nadal, made an authoritative start on centre court by breaking his Rochus in the second game.
The 23-year-old worked Rochus around the court with a string of whipped forehands and never allowed his Belgian opponent to get to the net in the first set.
Both players struggled on their serve in the second set, exchanging three breaks apiece in the first eight games, before former French Open runner-up Coria broke through in the ninth and then served out for the match.
Stepanek, who beat Henman in Vienna last week to claim his first win against the Briton in five attempts, broke serve in the first and fifth games on his way to a 5-3 lead in the first set.
PUSHED HARD
Henman pushed his opponent hard in the 10th game, but the Czech got the better of a quick-fire exchange at the net to hold his serve and take the first set 6-4.
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Stepanek fought back in the third, getting the crucial break in the eighth game and served out to love to take the decisive set 6-3.
Ninth seed Thomas Johansson of Sweden disposed of Juan Ignacio Chela 7-6, 6-3 and meets another Argentine David Nalbandian in his next match.
Croatian giant Ivo Karlovic, who beat Britain's Greg Rusedski on Tuesday, faces another big-hitter when he takes on second seed Andy Roddick.