Colin Kazim-Richards scored the only goal of the game as Blackburn stunned Arsenal 1-0 at the Emirates in the fifth round of the FA Cup.
Arsene Wenger's decision to rest a host of stars for Tuesday's Champions League clash with Bayern Munich backfired spectacularly and they now must win that competition to avoid an eighth consecutive season without a trophy.
Ironically, Blackburn got the only goal of the game in the 72nd minute of the match just moments after Arsenal had brought on Theo Walcott, Santi Cazorla and Jack Wilshere in a bid to avoid a replay.
They won't have to worry about that, though, as they struggled to turn mountains of possession and corners into goals as Blackburn scored with one of their few ventures forward.
After having been knocked out of Capital One Cup by League Two Bradford, it is the second cup humiliation against lower league opposition this season for Arsenal.
The goal that undid them was cruel on Arsenal though as Kazim-Richards actually scuffed his shot into the ground; but it spun into the corner of the net after the Turkish international had been the first to react when Wojciech Szczesny could only push Martin Olsson's half-volley into his path.
Arsenal threw everything at Blackburn from then until the final whistle but the Blackburn defence was expertly organised with Grant Hanley in particular standing out at the heart of the defence and Jake Kean also making some important saves in between the sticks.
Arsenal dominated possession in a drab opening 45 minutes but struggled to break down their Championship opponants.
As well as the big three that came on in the 72nd minute, Lukas Podolski and Aaron Ramsey were also on the bench, as Wenger decided to give some fringe players the chance to do the job.
The Gunners had an incredible 12 corners in the first-half but only really made an impact with two of them.
In the 24th minute Abou Diaby managed to get a free header on target but Kean was alert enough to push it over the bar.
Kean was again to the rescue five minutes later when he pushed away a header from Thomas Vermaelen that was looping towards the top corner despite Blackburn having men on the line.
Arsenal's best chance of the half though came from open play when Tomas Rosicky slipped in a perfect pass behind the defence for Gervinho. The Ivorian striker only had the onrushing Kean to beat but dragged a poor shot wide with the goal gaping.
Blackburn's only first half chance came after less than three minutes when Alex Oxlade-Chamberlain's defensive header from a Pedersen free-kick came to Marcus Olsson at the back post but he put it wide.
The second-half was similar to the first - lots of Arsenal possession but few chances.
Rosicky did almost break the deadlock in spectacular fashion in the 67th minute but he saw a superb shot cannon off the underside of the bar.
Wenger called on his big guns to try and find the elusive goal but the Emirates went into shock soon after the treble substitution when Blackburn took the lead with a rare attack.
Michael Appleton's men went back to their job of defending and were superb in the final 10 minutes as they withstood a barrage of Arsenal pressure.
Blocks, tackles and saves were all made in those closing stages as Arsenal just could not find the key to unlock the visiting defence.
It was a famous win for Blackburn who move into the last eight but the Arsenal team could hear nothing but boos as they departed the stadium as another trophyless season stares them in the face.
MAN OF THE MATCH
Grant Hanley (Blackburn) - Hanley was superb at the back for Blackburn and his performance was typically of his side's bravery.
Arsenal: Szczesny 6, Coquelin 6, Vermaelen 6, Koscielny 6, Monreal 7, Diaby 6, Rosicky 7, Arteta 5, Gervinho 5, Oxlade-Chamberlain 6, Giroud 5;
Subs: Wilshere 7, Cazorla 6, Walcott 6,
Blackburn: Kean 8, Orr 7, Dann 7, Hanley 8, Martin Olsson 7, Pedersen 7, Williamson 7, Lowe 7, Markus Olsson 7, Kazim-Richards 8, Rhodes 7;
Subs: Goodwillie 6, Bentley 6