Defending champion Andy Roddick recovered from a mid-match lull to reach the final at Queen's with a 6-3 2-6 6-2 win over Czech Radek Stepanek.
Roddick stays on course for his third straight Queen's final
Roddick broke Stepanek in the second game of the opener with a fiery passing shot and served out the set with ease.
The roles were reversed in the second, as some sloppy play from the American saw Stepanek break twice to level.
But Roddick stepped up a gear to claim the decider and set up a final with unseeded Croat Ivo Karlovic.
The American 22-year-old is aiming to wrap-up a hat-trick of Queen's victories on Sunday.
"He had me in a stranglehold there for a while so I had to really bear down and get myself pumped up for the third set," Roddick told BBC Sport after his win over Stepanek.
"I felt I returned a lot better in the third set."
Karlovic beat Swede Thomas Johansson 6-4 7-6 (9-7) to set up a final with Roddick.
The 6ft 10" player wasted no time, immediately breaking Johansson in the first set before calmly serving it out.
The Swede tried to respond in the second, carving out a set-point at 5-4 but the Croat hit a pair of aces to hold and enforce the tie-break.
Johansson saved two match-points but netted the ball to hand Karlovic the win and a surprise final spot.