Roger Federer cruised into the semi-finals of the Swiss Indoors by beating Nicolas Kiefer 6-3 6-2.
Federer broke Kiefer's first service game
Federer, who has won six titles so far in 2007, is now just two wins away from clinching the year-end world number one ranking for the fourth straight season.
The world number one is seeking his second consecutive title in his home town after winning in Basle in 2006.
He will play Ivo Karlovic after the Croat hit 38 aces to beat Tomas Berdych 6-7 (5-7) 7-6 (7-2) 7-6 (15-13).
"I will just try my best to concentrate on my own serve," Federer said when asked about the challenge of facing Karlovic.
"I do that against any player but it's even more important against him because you just want to stay with him and not fall behind."
The other semi-final will be contested by unseeded pair Jarkko Nieminen and Marcos Baghdatis.