Arsenio Halfhuid grabbed a hat-trick to shatter Millwall's hopes of progressing to the FA Cup quarter final as Aston Villa booked their place in the last eight of the competition with victory at Villa Park.
Halfhuid may have walked off with the matchball, but Scott Fitzgerald's young Lions walked off with their heads held high after contributing to an entertaining game, with the final scoreline hugely flattering the home team.
Having weathered an early Villa storm during which the hosts forced three corners in the first five minutes, it was The Lions who went on to dominate proceedings for much of the opening half.
A huge clearance by Kamil Tevfik on nine minutes saw Villa keeper Callum Barratt sprint some 45 yards out of his goal to boot clear from the onrushing Kiernan Hughes-Mason.
Three minutes later Millwall carved out their best chance of the half. Jake Gallagher did well to work an opening on the right and delivered a pinpoint cross met by Grant Ludford. His powerful header looked destined for the back of the net until Barratt somehow flung himself across goal to acrobatically avert the danger at full stretch.
Ludford was thwarted again on 18 minutes when his low free-kick was spilled by the keeper as Millwall continued to prise and probe an opening as the half progressed.
With The Lions looking confident and comfortable, it all went horribly wrong in a mad four minute spell before the break that reaped three goals for Villa.
Ryan Simmonds, who was the game's outstanding performer, capitalised on a lapse of concentration in the visiting defence and calmly rounded Wayne Drummond before firing home a 41st-minute opener.
Simmonds then turned provider for the first of Halfhuid's goals - a diving header that gave Drummond no chance.
Stunned by this double whammy, it became triple trouble just seconds later as Halfhuid added his second - and Villa's third - with another clinical finish.
Coach Fitzgerald had to rally his troops as they trudged off in a state of shock at the break - and to Millwall's immense credit - and the encouragement from plenty of travelling Lions fans - they had a real go in the second-half.
Matters weren't helped when John Marquis hobbled off injured 14 minutes after the restart, but the brave young Lions stuck to their task and continued to battle away.
Hassan Janneh looked odds-on to reduce the deficit when he broke through just past the hour-mark but with only the keeper to beat, his chipped effort agonisingly dropped onto the roof of the net.
His blushes were, however, saved by the assistant ref, who inexplicably and belatedly flagged for offside.
Play swung straight up the other end and Samir Carruthers nearly made it 4-0 for Villa, only to see his 20-yarder superbly tipped onto the bar by Drummond.
The Lions were handed a lifeline with 20 minutes remaining. Hughes-Mason was bundled over on the left flank, Tevfik's freekick was fumbled by Barratt and there was sub Ikenna Ofoche to convert from a tight angle.
The goal breathed fresh impetus and hope into the visitors. but it was Villa who were left breathing a huge sigh of relief on 76 minutes. Derrick Williams was penalised for handball and referee Dean Mohareb pointed straight to the spot. Sadly Hughes-Mason, who had scored in every round of the competition prior to this fifth round clash, saw his resulting penalty smack the crossbar before the ball was eventually cleared.
A second Millwall goal at that stage would have made for a very interesting finish, but it was Villa who finally ended any hopes of a late fightback when Simmonds provided his third assist of the night, which was swept home by Halfhuid for goal number four on 80 minutes.
But back came The Lions and it took another fine save by Barratt to keep out a thumping Gallagher drive as Fitzgerald's charges tried their best to ensure the scoreline gave a fairer reflection of their stirring efforts.
Unfortunately that crazy four-minute spell before the break left just too big a second-half mountain for Millwall to climb.

Aston Villa: Barratt, Grocott, Deeney, Devine, Williams, Carruthers, Lampkin (Nelson-Addy, 76mins), Blythe, Halfhuid (Poyser, 80mins), Simmonds, Roberts (Berry, 75mins). Subs not used: Coton, Taylor.
Booking: Devine (52mins)
Scorer: Simmonds (41mins), Halfhuid (44,45, 80mins)

Millwall: Drummond, McLaren, Fitzsimons, Tevfik, Hegarty, Beckles, Janneh (Adedipe, 75mins), Gallagher, Marquis (French, 58mins), Hughes-Mason, Ludford (Ofoche, 54mins). Subs not used: Stevenson, Farmer.
Bookings: Janneh (35mins), Hughes-Mason (35mins)
Scorer: Ofoche (70mins)

Ref: D. Mohareb