The Gunners have waited almost a year for this day to arrive. An opportunity to exact revenge on the side that mercilessly swept them aside from the Champions League last season in a devastating 6-3 aggregate defeat.

Last time around, Barcelona displayed the skill and experience that make them the best club in the world, and exposed the Gunners as mere pretenders, full of attacking flair yet devoid of the depth or class to truly compete at the highest level in Europe.

This year however, things are vastly different. While Barcelona remains a dominant force, winning 20 of their 23 matches in Spain's La Liga, boasting the world's best player in Lionel Messi, Arsenal have taken a leap forward, maturing into the legitimate contender that Arsene Wenger has long promised.

In last season's footballing lesson, the Gunners were fortunate to escape the first leg at the Emirates with a 2-2 draw, relying on much-maligned keeper Manuel Almunia's stellar game and an 85th minute penalty to send the Quarter-Finals back to Camp Nou. While managing a draw, Arsenal were utterly dominated, seeing only 35% possession as Barcelona held onto the ball for much of the match, allowing the Gunners only limited glimpses of it.

Upon returning to the Catalan giants' home however, Arsenal were a broken side, having lost captain Cesc Fabregas to a broken leg in the waning minutes of the first match, while also missing several other key players. Robin van Persie, Alex Song and William Gallas were all absent, forcing Wenger to put together a side that appeared woefully over-matched even before the opening whistle.

Though Nicklas Bendtner shockingly fired the Gunners in front in the 18th minute, Barcelona's class shone through as Lionel Messi then put on an unforgettable display with an incredible four goal performance that left the Gunners stunned. The Argentine wizard notched a hat-trick within 21 minutes, leaving Arsenal utterly dazed and searching for answers.

Arsenal still have holes in their central defense, but Swiss giant Johann Djourou is maturing before our eyes into a potential top-notch center-back that Arsenal have sorely lack in the absence of Thomas Vermaelen. Though the central pairing with Laurent Koscielny has appeared vulnerable at times, the two are slowly building an understanding that has appeared much-improved in recent months.

The primary difference now though, is the health of Cesc Fabregas, and the scintillating form of Dutch forward Robin van Persie. His frequent absences due to injury have often left a gaping hole in Arsenal's attack, but since returning from injury a few months ago, he has ascended to the top of offensive performers in Europe. He has long been recognized as a potentially dominant scoring threat, but injuries too often hamper his ability to perform at the level he is capable of. With 5 goals in his last 9 Premier League matches, van Persie is in top form and will undoubtedly provide Barcelona with an entirely new issue to deal with when facing the Gunners.

Additionally, Arsene Wenger has announced the shock return of French midfielder Samir Nasri, who had been doubtful due to a recent hamstring injury. The young maestro has developed into one of the best players in England this season, leading the Gunners in scoring and turning in fine performances week after week. His return is a massive boost for Wenger's side.

On the opposite wing, Theo Walcott has finally rounded the corner and has become a significant threat on the right side. Always blessed with the pace, the young Gunner's footballing brain has finally caught up, as the English burner has turned into far more well-rounded player than he has been in his young career. Walcott's blistering pace is always a danger for any defense, and he adds a dimension to Arsenal that Barcelona will struggle to defend at times.

Partnering with Cesc in the middle, 19-year-old Jack Wilshere, dubbed the "future of English football", has excelled in a box-to-box role, displaying his immense talents while thrilling football fans with rapid development. His speed, dribbling ability and precision passing will create a partnership in the middle that Barcelona never witnessed from the Gunners last season.

Alex Song, the strong defensive mid from Cameroon, was also absent last year, and his inclusion will be critical in front of the Arsenal central defenders. Song has developed into a well-rounded mid-fielder, capable of dominating his area while occasionally flying forward on unexpected offensive runs. His development has been one of the massively underrated reasons for Arsenal's continued success in 2010/11.

Despite Arsenal's incredible form and maturation, Barcelona still offers a formidable threat that the young Gunners will have to remain wary of. With Messi, David Villa and Pedro up front, Barca boast an incredible triple threat, capable of slicing open defenses in the blink of an eye. With Xavi pulling the strings and Andres Iniesta partnering with him in the middle, you can be sure that they will see much of the ball, waiting for the opportune moment to unleash hell on their opponents.

Helping Arsenal's chances will be the fact that stalwart defender Carlos Puyol is due to miss the match. His absence will create a void in the central defense that Arsenal will look to exploit at the Emirates.

Though this match-up was a nightmare last season, this year's version promises to be a thrilling affair that should be a feast for footballing fans everywhere. If Arsenal can keep Barcelona from holding onto the ball for 90 minutes, they have a chance to beat the Catalan masters at their own game.

If Barcelona underestimate the Gunners, Wenger's squad could very well stun the Spanish champions and prove to the world that they are indeed for real.