He was an IM. Four times Argentine Sub-champion (1989, 1992, 1993 and 2003).
From the mid-1970s to begin 2000s, Sergio Carlos Giardelli was one of Argentina's leading chess players. In 1974, in Manila he participated in World Junior Chess Championship and shared 6th–7th place.
From 1978 to 2005 he often participated in the Argentine Chess Championship finals and won five medals: four silver (1989, 1992, 1994, 2003) and bronze (1993).
Sergio Carlos Giardelli participated in World Chess Championships Zonal tournaments five times: 1982, 1987, 1989, 1993, and 2003.He was participant in a number of strong international chess tournaments. Sergio Carlos Giardelli won Mar del Plata Open Chess Tournament (1992), Champion of Circuito do Sol at Fortaleza (1994), and International Chess Tournament in Buenos Aires (2003).
Sergio Carlos Giardelli played for Argentina and Argentina B teams in the Chess Olympiads:
In 1978, at first board in the 23rd Chess Olympiad in Buenos Aires (+2, =2, -8),
In 1980, at first reserve board in the 24th Chess Olympiad in La Valletta (+7, =1, -4).
Wikipedia article: Sergio Carlos Giardelli