Hugo Rodallega’s late winner condemned Villa to their 10th home league defeat of the season as Fulham grabbed a survival lifeline.
The Colombian headed in with five minutes left to breathe life into the visitors’ hopes of Premier League survival.
Villa still need points to ensure their own top flight future despite Grant Holt’s goal cancelling out Kieran Richardson stunning opener.
Matt Lowton produced a brilliant goal-line clearance to deny Lewis Holtby but it was another wretched home game for Villa to leave them seven points above the bottom three
With Christian Benteke out for at least six months with a ruptured Achilles Holt was handed a start to spearhead Villa’s attack.
Lowton, Nathan Baker and Joe Bennett all started with Fabian Delph suffering an Achilles injury and was joined on the sidelines by the ill Gaby Agbonlahor.
A forgettable first half only produced two brief moments of note just after the half hour.
Bacuna latched onto Marc Albrighton’s superb pass to wriggle free of Pajtim Kasami only for David Stockdale to save his angled drive.
Brad Guzan then denied Cauley Woodrow after the striker seized on Baker’s loose pass but
Villa re-started well and Bacuna was denied when he burst down the right only for Stockdale to turn his drive onto the post.
But the half-time introduction of Rodallega had energised Fulham and they took the lead on 61 minutes with a blistering goal from Richardson.
Rodallega fed Ashkan Dejagah and his square pass came to Richardson, who fired in a brilliant first time effort into the top corner from 18-yards.
Villa rallied and levelled nine minutes later when Marc Albrighton’s corner was nodded into the bottom corner by Holt.
The game suddenly opened up and Fulham were denied a second by an incredible block by Lowton.
Rodellaga’s ball found Holtby unmarked in the area, he skipped round Guzan and looked set to make it 2-1 – but for a wonderful sliding clearance by Lowton on the line.
Weimann headed over and Aleksandar Tonev forced Stockdale into a decent save as Villa chased a winner – before disaster stuck.
Ron Vlaar had already denied Richardson before Fulham grabbed the winner five minutes from time.
Rodallega had been Fulham’s best outlet and won it when he latched onto Holtby’s cross to flick a header into the corner.