Alund capitalized on 16 double-faults by Chardy and outplayed him in a third-set tiebreaker to record a surprising 6-4, 4-6, 7-6 (7-5) decision in a 2-hour, 36-minute match.
He now goes on to face fellow Argentine Guido Pella in the second round.
Meanwhile, Brazilian qualifier Joao Souza advanced to face top-seeded Rafael Nadal with a 7-6 (8-6), retired, win over Spaniard Ruben Ramirez Hidalgo, while Argentina's Horacio Zeballos fell to Chilean qualifier Paul Capdeville, 6-7 (5-7), 6-0, 3-0, retired.
Zeballos was coming off an upset win over Nadal in last week's VTR Open final in Chile.
Spain's Albert Montanes got past Italian Paolo Lorenzi 6-4, 6-4 Wednesday.