Arsenal went into their clash with Leyton Orient in 2011 looking to keep alive their hopes of a double domestic cup success with a League Cup final against Birmingham City coming just a week after this FA Cup fifth-round tie at Brisbane Road.
The Gunners were also nine games unbeaten in the Premier League while they had just seen off Barcelona at the Emirates Stadium in the first leg of their Champions League second-round encounter, so confidence wasn't in short supply at the North London outfit.
As for Leyton Orient, they had also been nine games without defeat in League One, with victories away at Norwich City and Swansea City giving them the belief that they could cause a third successive shock in the competition.
Arsenal manager Arsene Wenger rested the likes of Cesc Fabregas, Samir Nasri and Jack Wilshere as he selected a starting lineup dominated by second-string players, while the notable inclusion in the Orient side was a start for former Chelsea midfielder Jimmy Smith.
Despite the wholesale alterations, Arsenal had enough experience within their ranks to suggest that they should comfortably overcome their opponents, but Orient imposed themselves impressively from the start, reducing the Premier League team to shots from distance.
Nicklas Bendtner and Marouane Chamakh were the first to try to test Orient stopper Jamie Jones, but their efforts lacked the power needed to help settle the nerves within the Gunners lineup.
Andrey Arshavin also found Jones equal to his sharp attempt that forced a near-post save, while at the other end, Charlie Daniels saw a driven effort from distance sail over Manuel Almunia's crossbar.
Despite their failings in front of goal, Arsenal should have established a half-time advantage shortly before the break when good work from Kieran Gibbs gave the left-back an opportunity to cross into the middle, but after he found Chamakh, the Moroccan sliced the ball wide of the post.
However, seven minutes after half time, Arsenal edged in front. Bendtner engineered an opening on the flank to cross for Tomas Rosicky, and the Czech Republic midfielder made no mistake with a header into the bottom corner.
The concession of the goal brought an instant response from the home team, who created an opportunity through Dean Cox, but his delivery was headed over by Alex Revell.
That reply appeared to remove any thoughts from within the Arsenal side that the game was done and dusted, and they soon came close to doubling their lead through Rosicky, who was denied by two excellent interventions from Jones.
However, with nothing to lose, Orient piled men forward, and after Revell had struck a shot wide of the target, they found an equaliser through a terrific individual effort from Jonathan Tehoue.
The French forward received the ball on the outside of the penalty area, before powering his way past two Arsenal defenders and firing the ball past Almunia from 10 yards to earn his team a lucrative replay at the Emirates Stadium.
However, in front of 59,000 supporters, Orient succumbed to a 5-0 defeat, with Bendtner finding the form that wasn't present during the first fixture to net a hat-trick against Russell Slade's men.
After being stunned by Birmingham in the Carling Cup final at Wembley, Arsenal bowed out of the FA Cup with a 2-0 defeat to Manchester United, and after Barcelona overturned a deficit in the Champions League, the Gunners were left to settle for a fourth-place finish in the Premier League.
As for Leyton Orient, six defeats in their final 12 league matches resulted in the O's missing out on a place in the League One playoffs by one position.
