Barcelona struggled mightily to take down Atletico Madrid a year ago and wound up losing the Spanish League title on the final day of the season because of this weakness. Barcelona will of course remember being eliminated from the Champions League in the quarterfinals against Atletico as well. A year ago, Los Cules simply had no means of passing around the defensively structured Atletico side.

But this season, the Catalonian club is finding a lot of luck against its emerging rivals. A 3-1 win in the league a few weeks ago was one big story, but the 1-0 win on Wednesday only added to Barcelona's resurgence. How have they done it? Is there a formula for success brewing here?

Lionel Messi

There is an old saying: "Barcelona goes as Messi goes." The team has undoubtedly done its best to try to overcome this moniker, but despite the additions of Luis Suarez and Neymar, this is still Messi's team and only he can make the side click at its finest. And Messi did just that in the last two matches against Los Colchoneros. Part of that success is coming from Messi adapting to playing on the right side of the pitch. For most of the season he seemed adamant about sticking in the middle as the false nine while Luis Suarez sat on the right side. It was working well for Messi but not so much for Suarez.

In the two Atletico games, La Pulga has managed to sit on the right side and wreak havoc on Guillerme Siqueira, who is Atletico's known weakness on defense. And in both games Messi has scored a goal; albeit the 1-0 win saw him miss a penalty before depositing the rebound into the back of the net. He also had an assist in the 3-1 romp. A year ago, Messi did not score any goals against Atletico Madrid, cementing his frustrating circumstances against Madrid's other club.

Aerial Duels

Remember when everyone talked about Barcelona being poor in the air? They are not dominant in the air, but they seem to know one thing or two when it comes to playing Los Colchoneros -- he who conquers the sky wins the match. Atletico Madrid, simply put, is the best aerial team in Europe. They have scored more aerial goals than any other team in Europe and seemingly destroy teams in this manner. The air is deceptive because a goal can come from virtually anything and anywhere and Atletico's prowess in this respect has made them almost unstoppable.

A year ago when these teams faced off in the Champions League at Madrid, Los Colchoneros had a decided advantage in aerials won (23-8). Barcelona's lead ball winner in the air was Jordi Alba who managed three aerial victories. Compare that to Raul Garcia who managed to win 12 aerial balls for Atletico and it tells you the whole story. Win the air in either zone and you have a chance to suppress a chance on your goal or earn a chance to score on the opponents'. Barcelona did win the aerial duel in the opening leg of that matchup, but the margin was minimal (10-9). Barcelona also had a slight edge in aerial duels 16-15 in their 0-0 draw at Madrid back in January 2014.

The other key game between these teams came on May 17 when Atletico claimed the Spanish League title with a 1-1 draw against Barcelona. As you might guess, Los Colchoneros dominated the air in that game 22-13 and the tying and ultimately defining goal in that match came on a header by Diego Godin off a corner kick.

What trend is emerging from this four-game sample? When Barcelona has neutralized or won the aerial duel against Atletico, they managed to salvage a draw. But when they lost the aerial duel, they lost one match and blew a 1-0 lead in a Championship deciding match.

Through two matches this year, Barcelona has neutralized Atletico's aerial advantage and come away with wins. The teams tied 15-15 on Wednesday in aerial duels while Barcelona had a 14-11 advantage in the 3-1 game earlier this year.

Fouls

Barcelona's play is predicated on one major idea -- keep the ball and tire the other team. But Barcelona's game requires patience and a slow momentum build. Any interruption to that flow can lead to a loss of concentration, mounting frustration and ultimately no success.

Atletico knows this and has feasted on shutting down Barcelona and Real Madrid's flow by virtue of creating fouls. Fouls kill the play and force a reset for both sides. By fouling the opponent, Atletico gets time to reorganize its defense and halt any buildup. Fouls also intimidate the opposition and force them to be ever more cautious in their approach.

Last year, Los Colchoneros dominated Barcelona by virtue of creating more fouls. They held substantial leads in this department in all meetings last year, but things have a swung a bit in Barcelona's favor this year. Barcelona has essentially fouled its rivals more often, but has also incurred fewer fouls from Atletico. Part of this has to do with Barcelona's style of play. Instead of sitting back and waiting for openings, the team is playing more direct against its opponent, forcing Atletico to scramble a bit more than expected defensively. There is not enough time to force fouls, thus making mistakes more rampant.

Barcelona's not backing down from the physical play might also lessen the intimidation factor that Atletico has prayed on over the last two years.

The Big Three (Or Other Two)

While Messi has stood out as a dominant force, he got some big help from Barcelona's other two big signings. Neymar and Luis Suarez each scored in the 3-1 romp, but were noticeably absent throughout the 1-0 win on Wednesday. These two games show exactly what superstars like these can do on their best and worst days. Barcelona is likely hoping for more of the former than the latter in coming showdowns with the Madrid side.

It is also essential to note that the most recent victory came as a result of a dubious penalty call, so Barcelona did not come away completely unscathed from this match. They are by no means dominating Los Colchoneros, but are winning the battles they need to win to be successful.