Robin van Persie salvaged Manchester United's UEFA Champions League dream as his hat-trick beat Olympiacos 3-0 and booked a last-eight spot.
The hosts had trailed 2-0 heading into the second leg, with manager David Moyes under huge pressure to produce a result, but the Scot avoided a Greek tragedy with the help of his prolific Dutch frontman.
Penalties have become a familiar sight at Old Trafford in recent days - United conceded three in the weekend Premier League mauling by Liverpool - and Van Persie put the hosts ahead from 12 yards when one went their way in the 25th minute after a foul by Jose Holebas.
The Netherlands striker doubled his tally on the stroke of half-time to level the tie on aggregate, before curling home a free-kick seven minutes into the second period to seal the win and a famous comeback.
The result takes United into the last eight for the first time since 2011, while Olympiacos have now lost on all 12 of their visits to England, conceding an average of three goals.
Moyes made four changes from Sunday's 3-0 Premier League defeat at home to fierce rivals Liverpool, bringing Rio Ferdinand and Ryan Giggs into an experienced starting XI, and it was United who did the early pressing.
Wayne Rooney was first to challenge visiting goalkeeper Roberto, with the Spanish shot-stopper electing to extravagantly punch clear from a free-kick, but United's Herculean task almost became even greater 15 minutes in, when Hernan Perez scooped the ball over after good work by Joel Campbell to set up the opportunity.
Rooney went agonisingly close to making the visitors pay for that miss as he headed against the left-hand post from Giggs' cross, with replays suggesting that Roberto may have got the slightest of fingertips to the ball.
But United broke the deadlock from the spot after 25 minutes - Van Persie powering home after he had been recklessly bundled to the ground from behind by Holebas.
Patrice Evra had Roberto diving at full stretch 10 minutes before the break, forcing the Spaniard into an impressive stop with a headed effort from Van Persie's corner.
David De Gea then made a crucial double save at the other end, first denying David Fuster's header and then recovering well to keep out Alejandro Dominguez's effort from close range.
And United were level in the tie in first-half stoppage time when Van Persie tapped home through the legs of Roberto after a cross from Rooney.
The Dutchman was single-handedly rescuing their hopes, and he completed his treble in the 52nd minute by curling a 20-yard free-kick around the Olympiacos wall and beyond a statuesque Roberto to give the home fans belief and lift a considerable weight off Moyes' shoulders.
However, he almost had the ball in the back of his own net shortly afterwards when Dominguez's free-kick deflected narrowly wide off his head.
The delicate nature of the scoreline was emphasised when Fuster's rifled effort straight at De Gea in the 67th minute had many a Mancunian heart in their mouth, with Olympiacos still only a single away goal from victory.
But United weathered a late storm to cling on to an important victory, although the sight of Van Persie leaving the field on stretcher late on will be of some concern.
|20||R. van Persie||25' 45+1' 52'|
|Coach: D. Moyes|
for A. Valencia 77'
for D. Welbeck 82'
for R. van Persie 90+1'
|Tonelli denies making death threats|
|Bosnich pleads guilty to reckless driving|
|Baines predicts ´huge future´ for Stones|
|Montreal Impact v America: Canadians draft in goalkeeper|
|Rakitic: Barca targeting treble|
|Australia´s Franjic quits Torpedo Moscow over unpaid wages|
|Kagawa: Dortmund owe Klopp a trophy|
|Zabaleta: Pellegrini deserves more respect|
|Liverpool will challenge next season - Rodgers|
|´Eternal pessimist´ Howe applauds Bournemouth´s impending promotion|
|Moreirense 1 Sporting Lisbon 4: Montero double keeps title hopes alive|
|Bournemouth 3 Bolton Wanderers 0: Howe´s men on the verge of the Premier League|
|Valencia 4 Granada 0: Hosts resume fourth place with thrashing|
|Turkish Super Lig Review: Besiktas back on top as Fenerbahce slip|
|Denis hit with five-game ban for dressing-room attack|
|Arabian Gulf League Review: Ajman relegated, Al Jazira close in on second|
|Zanetti: Icardi close to signing new deal|
|Pfaff hails Neuer´s consistency|
|Blanc: PSG can cope with physical demands|
|Bruce: Premier League must act on ticketing prices|
|Milan v Genoa: Off-field problems dominate build-up for Inzaghi´s men|
|Juventus v Fiorentina: Champions seek derby reaction with title in sight|
|Arminia Bielefeld v Wolfsburg: Hecking´s men in last-chance saloon|
|Real Madrid v Almeria: Rodriguez vows to fight until the end|
|Klopp ´an option´ to replace Guardiola at Bayern|
|Home form crucial for Premier League survival, says Bruce|
|Leicester City v Chelsea: Mourinho backs Pearson´s men to survive|
|Villarreal v Atletico Madrid: Marcelino´s men bidding to end winless run|
|Bundesliga title a footnote in Bayern´s grand plans|
|Robben back as Guardiola calls for focus|
|Mancini: Be patient with Shaqiri, Podolski|
|Klopp shrugs off Gundogan speculation|
|Run-in does not favour Barca - Luis Enrique|
|Mourinho takes further swipe at ´boring´ claims|
|Watford must spend smart, says Hyde|
|Allegri saddened by derby crowd trouble|
|Thompson ´mortified´ after throwing pole into team-mate´s leg|
|Hernandez not concerning himself with future|
|Stranzl to play no further part in Gladbach season|
|Rodgers keen to address lack of goals|
|Giroud cannot fire Arsenal to title - Henry|
|Do not destroy Sterling, says Campbell|
|Fournier: Lyon still dreaming|
|United performance Stones´ best - Martinez|
|Carver: Abuse from fans unacceptable|
|No shame in second place - Pellegrini|
|Humble Hazard thrilled with PFA honour|
|La Liga Preview: Real continue Barca pursuit against Almeria|
|Serie A Preview: Roma eye much-needed win|
|MLS Review: Toronto end drought, Red Bulls stay unbeaten|
|Chelsea to face Sydney in June|
|Liverpool can attract players - Rodgers|
|Bayern celebrate three-peat|
|Hernandez form forces Ancelotti´s hand|
|Hazard crowned PFA Players´ Player of the Year|
|Weidenfeller ruled out of Dortmund-Bayern semi-final|
|Weidenfeller ruled out of Dortmund-Bayern semi-final|
|Ligue 1 Review: Lens´ fate all but sealed, Lyon return top|
|La Liga Review: Hernandez rescues Real, Sevilla up to fourth|
|Paris Saint-Germain v Metz: Injuries prove a frustration for Blanc|
|Serie A Review: Juve made to wait as Parma fight another day|
|Celta Vigo 2 Real Madrid 4: Hernandez to the rescue again|
|Barcelona v Getafe: Iniesta keen to maintain momentum|
|Milan players in ´retreat´|
|United have opened the door for Liverpool - Van Gaal|
|Mourinho hits back at Arsenal fans´ ´boring´ jibes|
|Juve were own worst enemy in derby defeat – Allegri|
|Bundesliga Review: Gladbach victory ends title race|
|Udinese v Inter: Mancini braced for crucial week|
|Primeira Liga Review: O Classico tie leaves Benfica on the brink|
|Bayern Munich v Borussia Dortmund: Klopp prepares for final Klassiker|
|Russian Premier League Review: Zenit edge closer to glory, Amkar Perm off the bottom|
|Arsenal played with handbrake on - Wenger|
|Mourinho swerves Oscar discussion to hail Terry display|
|Bayern´s title confirmed as Wolfsburg stumble at Gladbach|
|Eredivise Review: Late leveller see Ajax secure Champions League berth|
|Arsenal 0 Chelsea 0: Oscar decision in the spotlight after stalemate|
|Van Gaal bemoans lack of fighting spirit|
|Van Gaal: United to assess Rooney injury|
|Torino 2 Juventus 1: First derby defeat since 1995 puts title celebrations on hold|
|Martinez hails Everton´s ´incredible mentality´ after beating United|
|Everton 3 Manchester United 0: Martinez outwits Van Gaal in comprehensive win|
|Dundee United 0 Celtic 3: Griffiths´ hat-trick edges champions closer to title|
|Alderweireld reveals he has broken shoulder bone|
|Hull City v Liverpool: Lovren expecting another test of patience|
|Leverkusen dealt Papadopoulos blow|
|Five in a row for Champions League winners Auckland|
|Vermaelen cleared to play in Barca run-in|
|Hughes buoyed by Odemwingie return|
|Allardyce hails Adrian heroics|
|Villa confident of staying up - Sherwood|
|Zorc rejects talk of Gundogan departure|
|´Happy´ Hazard rejects talk of Chelsea exit|
|A-League Review: Victory claim Premiers´ Plate|
|Pochettino hoping to strengthen|
|Pjanic critical of Roma spirit|
|Rodgers: No room for error now|
|MLS Review: Revolution win big as Dynamo, Kansas City draw|
|Garcia rues sloppy build-up play|
|Jokanovic eyes title for Watford|
|Blanc: PSG have moved on|
|Hazard worth ´£100m each leg´ - Mourinho|
|Ferguson: United boss can break my trophy record|
|Levante leap clear of La Liga drop zone|
|Primeira Liga Review: Gil Vicente claim vital win, Estoril and Rio Ave held|