British number one Cameron Norrie can no longer qualify for the season-ending ATP Finals in Turin.
The seventh seed defeated Australian James Duckworth 6-2 6-7 (4-7) 7-5 and will face world number one Novak Djokovic in the last four.
Norrie still intends to travel to Turin as one of two alternates.
The 26-year-old world number 13 was knocked out in Paris in the last 16 by American Taylor Fritz, who was then beaten 6-4 6-3 by Djokovic in the quarter-finals.