A cheeky backheel goal ended Sydney FC's Asian Champions League hopes, with the Sky Blues losing 1-0 away to South Korea's Ulsan Hyundai on Tuesday.
The result left winless Sydney bottom of the four-team group with three points from five matches with one round to go.
Sydney are three-points behind China's second-placed Shanghai SIPG, who win the tie-breaker with the Sky Blues, having scored more away goals in their two head-to-head games.
They will now focus on Sunday's home A-League semifinal with old rivals Melbourne Victory.
It was the latest in a series of frustrating Champions League nights for Sydney, who have won just one of their last 15 matches in the competition.
As they did in most of their four previous games, Sydney had a good share of the match, but let points slip away by failing to take chances.
The sole goal of the game came in the 59th minute when American midfielder Mix Diskerud initiated a counter attack with a flick and finished it with an equally clever and well executed backheel.
Sydney had several chances to equalise with Iranian international Reza Ghoochannejhad lifting the ball over the Ulsan goalkeeper Oh Seung-Hoon in the 90th minute, but the weak shot was cleared just short off the line.
Even before that, Sydney were guilty of squandering good opportunities.
Five minutes after the goal, Anthony Caceres wasted a glorious chance, blasting a close range shot straight at Hoon, who knew little about the strike which crashed off his chin to safety.
Shortly after, substitute Daniel De Silva fired another shot straight at Hoon, who blocked the midfielder's attempt with his legs, Josh Brillante slammed a fierce effort just wide and Paulo Retre was off target with a header,
Recalled left-back Michael Zullo was the creator of Sydney's three best chances in the first 50 minutes, swinging over some fine crosses.
Retre, Ghoochannejhad and Adam Le Fondre all failed to finish off Zullo's good work.
Redmayne saved Sydney again when he palmed away a fierce 57th minute shot from Park Joo-Ho, but could do nothing about the goal a couple of minutes later.