ROME, May 15: Michael Chang sent world number one Pete Sampras tumbling out of the Italian Open in the third round yesterday while Marcelo Rios gave another awesome display of his abilities to dispatch Thomas Muster in less than an hour.Chang triumphed, 6-2, 7-6 clinching the match 8-6 in a thrilling tie-break as top-seed Sampras once again struggled to adapt his game to Rome's red clay courts.Astonishingly, Chang easily out-served his fellow American, never double-faulting and hitting 11 aces to Sampras's five.Chang waltzed through the first set and threatened to break serve in the third game of the second, as Sampras wrestled with his mind and his game.The result means Sampras has still never taken a set off Chang on clay. The two men had met only once before on the surface - at the 1989 French Open when Chang won 6-1, 6-1, 6-1.Rios now faces former Wimbledon champion Richard Krajicek, who came through a gruelling three-setter in the afternoon sun to beat sixth-seed Yevgeny Kafelnikov 6-2,3-6, 7-6.French Open champion Gustavo Kuerten brushed aside the youngest player in the tournament, Germany's Tommy Haas, to reach the quarter-finals on his first appearance in Rome.Hingis signals warningBERLIN: Martina Hingis warned she is ready to add the only Grand Slam trophy missing from her collection when she beat Iva Majoli in 49 minutes at the German Open yesterday. The 17-year-old Swiss world number one's 6-2, 6-1 win carried her into the quarter-finals and avenged her surprise defeat in the final of the 1997 French Open.