World number two Roger Federer eased into the Gerry Weber Open final with a straight-set victory over Ivo Karlovic.
The Swiss top seed won 7-6 (7-3) 7-6 (7-4) to move closer to a record eighth title in Halle, Germany.
Karlovic, 36, hit 45 aces - the most in a three-set ATP Tour match - against Tomas Berdych in the last eight.
Federer, 33, was unable to secure a single break point against the Croat but won both tie-breaks to set up his 10th appearance in the event's final.
A brilliant backhand return followed by a Karlovic double fault secured Federer the first set and he went on to seal victory after one hour and 28 minutes with a backhand volley in the second tie-break.