Federer is three wins from matching Jimmy Connors's all-time record of 174 victories on grass.
HALLE, Germany (AP) Roger Federer defeated Matthew Ebden 7-6 (2), 7-5 to reach the semifinals of the Gerry Weber Open grasscourt event on Friday.
The defending champion was made to work hard by Ebden, who saved five of the eight break points he faced and led 5-3 in the second set.
Federer, who saved two match points against Benoit Paire the day before, recovered to go 6-5 up and then broke serve to set up a meeting with American qualifier Denis Kudla, who beat Japan's Yuichi Sugita 6-2, 7-5.
Roberto Bautista Agut will play Borna Coric in the other semifinal.
Bautista Agut defeated Karen Khachanov 6-3, 6-7 (3), 6-3, while Coric prevailed 7-5, 6-3 against Andreas Seppi.
Federer, who claimed his 18th grasscourt title in Stuttgart on Sunday, is three wins from matching Jimmy Connors's all-time record of 174 victories on grass.
The Swiss great extended his grasscourt winning streak to 19, including last year's titles at Halle and Wimbledon.
Federer is bidding for a record-extending 10th trophy in Halle.