The Crows' finals ambitions ended with a heartbreaking 11.8 (74) to 10.13 (73) defeat to the Swans at a rain-drenched Adelaide Oval on Saturday night.
Seventh-placed Sydney, who lost livewire Tom Papley to hamstring tightness, were 44 points up late in the second quarter and led by 32 at three quarter-time.
But Adelaide stormed in the last quarter, booting 4.8 to 0.1 only to fall just short.
With 80 seconds remaining, Crow Ben Keays thought he'd kicked a goal and given his side the lead.
But as Keays and teammates wildly celebrated, the goal umpire signalled a behind for the ball hitting a goal post.
The umpire didn't seek a video review and replays later appeared to show the ball didn't hit a post.
Coach Nicks said from his bench viewing point: "I can't tell you whether it was a goal or not".
"What I can tell you, my understanding is that we review those moments, especially at the end of games," Nicks said.
"We've just put trust in the process now. So as a footy club and as a coach, that's all we can do."
Swans coach John Longmire deadpanned: "Oh, does it?" when told a replay showed his team may have dodged a proverbial bullet.
But Nicks highlighted Adelaide's first-half struggles as the reason for defeat: the Swans kicked nine goals to two to create a 44-point lead late in the second term.
"Our first half was as good as we have played for a long time," Longmire said.
Sydney hold seventh spot by two premiership points ahead of their SCG clash against top-four fancy Melbourne.
"We have still got a bit of work to do next week, the good thing is we have got our destiny in our own hands to a degree," Longmire said.
The brilliant Papley faces scans on his injury.
"His hamstring was a bit tight and he wasn't moving that well," Longmire said.
"We will see how he is tomorrow."
Swans winger Errol Gulden continued his fine season with 30 disposals, Chad Warner (25 touches) was a standout and Oliver Florent (21) and Tom Papley (one goal) had patches of influence..
Isaac Heeney's three-goal scoring polish in attack was supported by Hayden McLean (two goals) while Nick Blakey (21 disposals, seven marks) was prominent in defence.
Adelaide's Taylor Walker and Josh Rachele kicked two goals each and Crows on-ballers Rory Laird (31 possessions), Matt Crouch (26) and Jake Soligo (28) revelled in the wet.
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