British wildcard Ryan Peniston's fine run at Queen's is over after a tight loss to Filip Krajinovic in the quarter-finals.
The world number 180, bidding to reach the semi-finals in his first ATP Tour event, lost 4-6 6-3 6-3 to the 48th-ranked Serb on a sweltering afternoon.
The 26-year-old started the stronger of the two but could not keep out the experienced Krajinovic.
Krajinovic will play Marin Cilic or Emil Ruusuvuori next.
Peniston was the last Briton in the singles draw, having registered eye-catching victories over top seed Casper Ruud and world number 46 Francisco Cerundolo.