Stewart Kean blew a 90th-minute penalty as 10-man Stenhousemuir went down 1-0 at Arbroath in the quarter-finals of the Ramsdens Cup.
Scott Robertson headed the hosts into a first-half lead before John Gemmell saw red for Stenhousemuir, who were gifted a chance to level late on only for Kean to fire over from the spot - sending Arbroath into the semi-finals.
After a thrilling opening half-hour which saw the home side hit the crossbar twice, Robertson broke the deadlock when he nodded in from Paul Sheerin's corner via Alex Keddie's assist.
The visitors' task was made even harder four minutes after the break when Gemmell was shown a straight red for a foul on Stuart Malcolm.
But Stenhousemuir wasted their opportunity to level from 12 yards after Keddie upended Kean, who duly blazed over.