After winning a remarkable first set which saw seven breaks of serve, the world No 1 ran away with the second set to reach the semi-finals after 57 minutes.
Sampras and Agassi have met in three grand slam finals, the last in 1995 when Sampras won the US Open in four sets. Agassi, who needs some favourable results over the next few weeks to make sure of his place at next month's season-ending ATP World Championship, was a far from his best.
After both Americans held their opening service games, there were seven breaks in the next eight. Sampras, however, kept his nerve, clinching the first set after 36 minutes when Agassi hit a wide forehand. The Las Vegan, ranked ninth in the world, never fully recovered his composure as Sampras ran away to a 5-0 lead in the second set on his way to victory.
"I knew from the first ball contact today, the first exchange, that I felt good," Sampras said. "He just wasn't in the match today. I think he suffered a letdown. I've played at this level before, but today Andre just wasn't there. Everything fitted together - my serve, my returns, everything."
In today's semi-finals the three-times Wimbledon champion will meet the Dutchman Jan Siemerink, who beat the fifth seed Goran Ivanisevic 6-3, 7-6 in the first quarter-final of the day.
The ATP tour chief executive officer, Mark Miles, has accused organisers of being selfish and destructive with their decision to move the Grand Slam Cup from December to earlier in the season.
"It's a self-centred decision," Miles said. "It is putting another big event in the middle of a crowded season. It puts an obstacle to the flow of events."
Next year organisers plan to stage the event in September, shortly after the US Open, which is certain to raise the tournament's profile.Reuse content