Despite suffering many nagging injuries over the past few years, Robin van Persie has distinguised himself as a world-class striker.

Van Persie's contributions to Arsenal and the Netherlands have been immeasurable. He not only scores with relative ease, but he helps create opportunities for other players, and his mere presence on the field causes opponents to adjust their defensive formations.

That's why Arsenal's loss to Barcelona in Champions League is so baffling as to how a player so important to a team's success can so quickly transform into a reason for its downfall in an important match.

Pre-match questions regarding van Persie's knee, which he injured upon scoring in the League Cup final against Birmingham, persisted for days. Whether van Persie would play was the topic of intense discussion.

The other question, perhaps insufficiently examined, was how effective would van Persie be if he played. The prospect of forward Nicklas Bendtner playing at full strength would perhaps have been a better option than van Persie in poor form, and without the possibility of playing the full 90 minutes.

Alas, manager Arsene Wenger decided he would announce van Persie's status for the game at the latest possible time to make sure the Dutch forward's knee was fully fit.

But then there was the whole issue of the game itself. Had van Persie been at his best, and had Arsenal been injury-free and playing at their highest level, a victory at Camp Nou against dominant Barcelona would have still been unlikely.

Indeed, for Arsenal to legitimately have a chance to win, they would need to be at their best, and perhaps have some breaks go their way.

The opposite happened inside the first 20 minutes of the match. A ruptured tendon in Wojciech Szczesny's finger led to a first-half goalkeeper substitution. Van Persie, who was likely to be subsituted in the second half, would now be positioned to be one of the two final substitutions rather one of three.

Through no fault of his own, van Persie was virtually non-existent in the first half. Barcelona employed their typical strategy of methodical ball possession to bait their opponents into chasing rather than defending. When the Gunners won possession, they failed to challenge the Catalans' defense with efficient passing to create true scoring chances.

Van Persie was basically denied the chance to prove his worth and fitness. However, one might argue that van Persie made minimal effort to be active, and that contributed to his lack of production.

As the match unfolded towards the end of the first half, the results were not good for Arsenal and van Persie.

When Barcelona midfielder Javier Mascherano brought down Arsenal's Jack Wilshere on a hard but somewhat innocuous challenge, the two teams began to jaw at one another as Wilshere remained in pain.

The confrontations turned physical when Barcelona's Eric Abidal put his hand around van Persie's neck.

Moments later, when the game resumed, van Persie did what he should have known not to do: he retaliated.

A blatant and malicious elbow on Dani Alves earned van Persie a yellow card, but a red card may have been justified. Van Persie needed to be on his best behavior because two yellow cards would be catastrophic for Arsenal. Not only was the striker hit with a yellow, he was hit with a first-half yellow.

It was a sign of Arsenal losing composure when poise and maturity was a vital asset. What followed was a Lionel Messi goal off an uncommonly risky pass by Cesc Fabregas.

The injury-plagued midfielder, like van Persie, needed his decision-making skills at their best to compensate for not playing at 100 percent fitness.

Instead of going into halftime scoreless, which would have been a relief for Arsenal, the Gunners surrendered a goal that could have very easily been avoided.

The second half was a perfect opportunity for Arsenal to move forward with a perhaps more opened up field, and make the right adjustments to the first half failures.

The Gunners also could have used a break or two. They needed some type of Barcelona mistake to capitalize on, even if it was small.

What resulted was, in fact, an enormous break. Off a corner kick in the 53rd minute, Barcelona defensive midfielder Sergio Busquets headed the ball into his own goal. Suddenly, Arsenal was in the current position of advancing to the quarter-finals off away goals.

Just a few minutes after that gift, and perhaps before Arsene Wenger could consider making his second substitution, the game basically ended for Arsenal.

Van Persie was given a second yellow card for a play where he struck the ball well after the whistle. Van Persie's claims that he didn't hear the whistle because it was drowned out by the noise of the sold-out crowd made perfect sense, but referee Massimo Busacca stood by his errant call, which basically meant the match was over.

Barcelona's passing attack was giving Arsenal fits all match, and with the Gunners down a man, it wasn't a matter of whether Arsenal would concede a goal, but rather when it would concede a goal, and how many.

What transpired after van Persie's yellow card was highly expected. Barcelona scored twice to finish off Arsenal. It's almost surprising that Barcelona scored just two goals, and that it took 16 minutes to get the second one.

Had the second yellow card been assessed a little later in the match, Wenger would have made the obvious move and substituted van Persie out, still leaving the manager with one last substitution for perhaps the last 20 minutes.

But that's not what denied Arsenal the chance to maintain the 1-1 draw.

Van Persie's first yellow card should never have been committed, and Arsenal should never have been playing a man down.

Abidal had no business putting his heand on van Persie's throat, but van Persie should have known better than to retaliate when losing him to yellow cards would basically spell doom for Arsenal's chances of advancing to the next round.

Though van Persie's first yellow card was wrong, Arsenal should be grateful they have such a gifted goal-scorer. When famed forward Dennis Bergkamp played for Arsenal from the mid-1990s through the mid-2000s, the club saw some of its most successful seasons.

In van Persie, Arsenal has a player who was groomed by Bergkamp and whose style of play most mirrors him compared to all other players in the world.

But van Persie's first yellow card was such a thoughtless act, that the referee's poor decision on the second yellow is almost inconsequential. Van Persie, a standout guy on and off the field, will likely make amends for the lapse of judgement, but the damage has been done.

Arsenal needed to play a nearly error-free match to defeat Barcelona.

Instead they got an enormous error and it perhaps cost them a run at the Champions League title.