Nalbandian prevailed in a close first set and played flawlessly in the final two to cruise to a 7-5, 6-0, 6-0 victory at Rod Laver Arena in the quarterfinal round.
The 24-year-old Argentine, who lost in the quarterfinals in each of the last two years, captured the last 14 games of the match to end Santoro's surprising run in Melbourne.
The world No. 4 Nalbandian will next face the winner of Tuesday's quarterfinal match between seventh-seeded Croat Ivan Ljubicic and unseeded Cypriot Marcos Baghdatis, who stunned second-seeded American Andy Roddick on Sunday.
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