The sixth seed was in superb form as he thrashed Argentina's Mariano Zabaleta 6-2 6-1 in Indianapolis.
And he will now face top-seeded Brazilian, Gustavo Kuerten, who earlier defeated Ivan Ljubicic, of Croatia, 7-6 6-4.
Meanwhile, Australian Lleyton Hewitt bucked his winning trend with an upset loss to Moroccan Younes El Aynaoui 6-3 6-7 6-3.
The 20-year-old admitted that he is in need of a short break before the US Open.
"It was windy today and I couldn't get any rhythm.
"But I had some tough matches last week and a bit of a chest infection. I didn't feel so great in the second round against Taylor Dent here."
Goran glory
Hewitt described his two-hour, 12-minute loss as "one of the worst matches I've played."
But there was joy for Marat Safin and Goran Ivanisevic.
Second-seeded Safin, of Russia, rallied from 2-5 in the opening set and never looked back as he put out Spain's 16th seed Tommy Robredo 7-6 6-1.
Wimbledon champion, Goran Ivanisevic, the 10th seed, claimed his 12th victory in 13 matches with a win against Arnaud Clement, of France, 7-5, 7-5.