Nicklas Helenius scored his first competitive Villa goal - but it wasn't enough to prevent a shock FA Cup exit at the hands of Sheffield United.
The Danish striker, on as a sub for Aleksandar Tonev, drilled home a low 75th minute-shot to cancel out Jamie Murphy's deflected 19th-minute opener for the League One outfit.
But with a replay looming, Ryan Flynn delivered the knockout blow with an unstoppable drive nine minutes from the end.
Villa's problems began even before kick-off.
They were forced to make a change to their line-up when Nathan Baker was ruled out by a hamstring problem.
Rather than risk him, manager Paul Lambert moved Matt Lowton into central defence alongside Ciaran Clark, with Leandro Bacuna switching to right-back and Tonev, originally named among the subs, drafted into midfield.
Clark was handed the captain's armband in the absence of Ron Vlaar, Gabby Agbonlahor and Brad Guzan, but didn't have the best start in the role as United stood firm in the opening stages before taking the lead.
Murphy cut in from the left hand corner of the penalty area, and although his right-foot shot was well struck, the ball took a deflection and looped over keeper Jed Steer into the net.
The setback spurred Villa into a spirited response, with Tonev and Andi Weimman both having shots blocked as the home side went in search of a quick equaliser.
Murphy again tried his luck with a low shot from 25 yards but this one was wide by some distance, as was Tonev's effort at the other end just past the half hour mark.
Then Marc Albrighton's cross from the right was just too far for Christian Benteke to capitalise, the striker succeeding only in knocking the ball back across the goalmouth, where keeper George Long collected comfortably.
Villa enjoyed a sustained spell of pressure just before half-time, culminating in a right-wing Albrighton cross.
Benteke managed to get above his marker for a header but was unable to get any direction on the ball - and he suffered the same fate in added time following another high ball into the penalty area.
The Blades opened the second period in positive mood, Steer twice saving well from Flynn within three minutes of the resumption.
The keeper pushed away Flynn's right-foot angle drive for a corner and then clutched the midfielder's 25-yard left-footer.
Villa's best efforts at that stage were crosses from either flank.
Long tipped away Albrighton's dipping centre from the right before Tonev's left-wing delivery deflected on to the top of the net for a corner.
But the visitors still looked dangerous going forward and Clark was forced into a hurried clearance after Steer found yet another Flynn drive too hot to handle.
In the 70th minute, Benteke found himself in a good position just inside the penalty area but his left-footer was held by Long, who tipped away Bacuna's curling cross from the right a few minutes later.
Five minutes later it was all-square, Helenius lashing home right-footed from 15 yards after the ball had ricocheted around the goalmouth after Albrighton had played the ball in from the right.
But after Weimann's shot had deflected over the bar, United were back in front in 81st minute, Flynn working his way along the edge of the area before unleashing a fierce left-foot drive which left Steer helpless as it flew into the top corner.
Weimann volleyed just wide in stoppage time before Benteke was off target with an overhead kick.
But it was too little, too late.
Villa: Steer; Bacuna, Lowton, Clark, Luna; Albrighton, Westwood,Delph, Tonev (Helenius 60); Weimann, Benteke. Unused subs: Guzan, El Ahmadi, Sylla, Bowery, Gardner, Donacien.
Sheffield United: Long; McMahon, Maguire, Collins, Hill; Flynn, McGinn, Doyle, Murphy (Miller 90); Porter (Kennedy 90), Baxter (Coady 80). Unused subs: Howard, Cuvelier, Brandy,Calvert-Lewin.