World number one, Martina Hingis, has made it through to the women's quarter-finals at the Indian Wells tennis tournament in California. However, fellow Swiss player, Roger Federer, didn't fare as well on Monday.
Federer lost the first round match of the Masters Series against Kiefer, 3-6, 7-5, 6-1.
"I missed a straight shot during the 4-2 tie break," said Federer following his defeat, "and during the second game, I had the sun in my face". He added that he committed two double faults and that the match turned against him in "a matter of seconds".
There was good news for Switzerland on the women's front, however. The Swiss player and world number one Hingis beat Austria's, Barbara Schett, 6-3, 7-6, for a place in the women's quarter-finals.
Hingis won the match against Schett after disputing a tie-break. Her next opponent will be determined by the outcome of a match between Germany's Anke Huber and Italy's Silvia Farina-Elia.
On Tuesday, Swiss player Marc Rosset is scheduled to go up against Sweden's Thomas Enqvist.
The Indian Wells women's title is worth $2 million while the men's title is worth $3 million.
swissinfo with agencies