Andy Murray kept on track to claim a record fifth title at Queen's Club by beating fellow Briton Aljaz Bedene 6-3, 6-4 to reach the quarterfinals on Thursday.
John Isner of the U.S. fired 43 aces and held 10 match points but lost to Gilles Muller of Luxembourg 3-6, 7-6 (16), 7-6 (7).
Murray faced a break point in the opening game but then broke to lead 5-3 and served out the set. Murray maintained the pressure in the second set, and despite failing to convert four break points to lead 1-0 and dropping his own serve after breaking for 2-1, a further break for 4-3 proved decisive.
Murray's next opponent will be another countryman, Kyle Edmund, who received a walkover when Frenchman Paul-Henri Mathieu withdrew with a wrist injury.
Isner seemed to be set for victory against Muller, holding six match points in the second-set tiebreaker, but Muller leveled the match on his fifth set point. In the final set, the American held off five break points as the set moved to another tiebreaker, but then failed to capitalize on a further four match points.