Kiefer conquers Norman

Sweden’s Thomas Johansson, a 91st-ranked longshot, beat Australian qualifier Wayne Arthurs 6-4 6-7 (7-9) 6-3 6-4 and will next face 1999 Open runner-up Todd Martin, who advanced with his second stunning fightback in as many years.

Safin, Kiefer and Johansson equaled their best Grand Slam showing and Martin matched a 1999 fourth-round miracle comeback to beat 1998 French Open champion Carlos Moya of Spain 6-7 (3-7) 6-7 (7-9) 6-1 7-6 (8-6) 6-2.

In Tuesday’s quarter-finals, Sampras faces nemesis Richard Krajicek, who leads their rivalry 6-3, and Aussie 19-year-old Lleyton Hewitt meets France’s 37th-ranked Arnaud Clement in a battle of Slam quarter-final debutantes.

In the women’s section, World number one Martina Hingis beat Monica Seles for the sixth time in a row to reach the semi-finals, setting up a Friday showdown with Venus Williams and her 24-match win streak.

The 19-year-old Swiss top seed toppled Seles 6-0 7-5 while 20-year-old Wimbledon champion Williams struggled past eighth seed Nathalie Tauziat 6-4 1-6 6-1 to set up their third Flushing Meadows matchup in four years.

Hingis is 9-6 against Williams, including US Open triumphs in the 1997 final and 1999 semi-finals. But Williams won their most recent encounter in July at the Wimbledon quarter-finals.

Williams bottomed out, literally and figuratively, against Tauziat by making 31 unforced errors on the court and an embarrassing one off it, landing on her rear after missing her chair as she went to sit during a last-set changeover.

Seles fell to 0-10 this year against the WTA’s four top-ranked players and 2-11 lifetime against Hingis, who saw the match as a good indicator of her game looking ahead to Williams.

Hingis won the first set in 14 minutes, allowing Seles only six points. It was the third love set in a row Hingis had taken from Seles, who made three double faults and 12 unforced errors in the span.

Defending champion Serena Williams will face US Olympic teammate Lindsay Davenport in the quarter-final on Tuesday. The winner meets either 18-year-old Russian Elena Dementieva or German 10th seed Anke Huber in the other semi-final.