A goal from Colin Kazim-Richards was enough for Blackburn to register a 1-0 victory at Emirates Stadium, meaning that the Gunners will have to win the Champions League if they are to end their seven-year hunt for a trophy.

Arsenal had plenty of the ball in the opening stages, but despite a succession of corners, could not create any clear opportunities until the 24th minute, when Abou Diaby forced a good save from 22-year-old goalkeeper Jake Kean with a header.

Kean was called into action again minutes later, when a deflected defensive header looped towards his goal, but the keeper clawed it out for yet another corner.

With the first half drawing to a close, the clearest opening of the match came and went as Gervinho was threaded through by Tomas Rosicky, only to place his shot wide of Kean's post, having sent the keeper the other way.

The first 45 minutes drew to a close with the sides level, and the game in need of something to ignite it in the second half.

There was early pressure from the Gunners in the second half, but they still weren't creating anything of note as the visitors' defence held strong.

The 67th minute heralded the first real moment of note in the second half, as Rosicky struck a stunning effort from 25 yards that crashed back off Kean's crossbar, while Gervinho was sent through on goal only to be denied by a last-ditch tackle from Grant Hanley.

With 20 minutes to go, Wenger made his move, with Jack Wilshere, Theo Walcott and Santi Cazorla replacing Gervinho, Rosicky and Alex Oxlade-Chamberlain.

But it didn't have the desired effect as just one minute later, the Gunners were split open by a long ball.

Martin Olsson's strike was pushed out by Szczesny, but only back in front of goal, and Kazim-Richards was on hand to bounce an awkward shot home via the post.

The stage was set for a Gunners onslaught, and they duly obliged with the visitors dropping deeper and deeper in a bid to protect their lead.

But despite their dominance, Blackburn held on to progress to the quarter-finals.

Meanwhile, a last-minute strike from Matt Smith helped Oldham rescue a 2-2 draw at home against Everton.

The League One side took the lead through Jordan Obita, but Victor Anichebe struck for Everton in the 24th minute to level the score as the teams headed into half-time.

Phil Jagielka gave the visitors a hard-fought advantage three minutes after the interval when he rose to meet a corner from substitute Kevin Mirallas and it looked like Everton were on their way to the final eight.

But the hosts kept pushing forward, and they must have been cursing their luck as Lee Barnard witnessed his close-range strike deflect agonisingly wide of the post before Tim Howard was called into action again to deny Robbie Simpson.

Undeterred, Oldham fought desperately to try and provide the sting in the tail, and it was Smith who was once again the headline maker, leaping highest to meet a Jonathan Grounds delivery and spark jubilant celebrations from the home crowd.

In Saturday's other match, Millwall avoided a potential banana-skin to advance to the last eight with a comfortable 3-0 win over non-league Luton Town at Kenilworth Road.

First-half goals from James Henry and Rob Hulse and a second-half strike from Danny N'Guessan ensured the Lions progressed to the quarter-finals of the tournament for the first time since they were beaten in the 2004 final by Manchester United.

Barnsley are also through to the quarters after surviving a second-half MK Dons fightback to secure a 3-1 victory at Stadium MK.

The visitors roared out of the blocks and, inspired by midfield playmaker Jacob Mellis, established a two-goal lead through Chris Dagnall and Marlon Harewood inside 20 minutes.

Lifeless before half-time, the Dons improved after the break but Dean Bowditch's goal was all they could muster and Dagnall added a late third on the counterattack to seal the win.