Ahead of their Copa del Rey matchup, what are the key elements that could make this a series for the ages?

Barcelona and Atletico will meet for the second time in less than two weeks, this time to determine which side will make it through the Copa del Rey Quarterfinals. Recently, this rivalry has lifted La Liga's competitiveness, and it will surely bring fans lots of fun and controversy, with Lionel Messi apparently returning to his old form, and with Fernando Torres recently scoring his first brace against Real Madrid playing at Santiago Bernabeu Stadium.

Los Blaugranas and Los Colchoneros are two of the biggest teams playing in La Liga. Atletico's recent comeback to top level football ended the dominance exercised by Los Culés and Real Madrid in the recent years, and they surely can thank Diego Simeone for it. After the Argentinian's arrival with Atletico, the team was able to create a six game streak without being defeated. During that run, Simeone's men played the last game of the 2013-2014 season at Camp Nou, winning La Liga after a 1-1 result. Their streak ended on January 11, when Barcelona's MSN trio lifted them over Los Colchoneros with a 3-1 result. Considering every game played in the new millenium, Barcelona has registered 16 wins, topping Atletico's 9, with nine drawn games. Atletico will try to close the gap between them , and they surely have what it takes to make Barcelona nervous.

Last eight games between Barcelona and Atletico.

THE MESSI FACTOR: HOW BARCA'S NO. 10 PERFORMS AGAINST ATLETICO

Lionel Messi has scored at least one goal against every team he's faced, but Atletico's net has always been one of his favorite targets. The Argentinian superstar has scored a whopping 21 times against Los Colchoneros, including three hat-tricks. Barcelona has never lost a match against Atletico if Messi scores. During their six-game streak against los Culés, Atletico were able to deny Messi any goals, and maybe that's the reason why Simeone's men were able to put together such a streak. If Messi turns on the "Nightmare mood" against Atletico, then Los Blaugranas could be in for an easy series.

Goals scored by Messi vs Atletico.

EL NIÑO IS BACK: CAN TORRES HURT BARCA'S DEFENCE LIKE BEFORE?

One of this winter's most anticipated transfers was the one that involved Fernando Torres. The Spanish striker returned to his childhood club and already made a positive impact for Simeone's crew, scoring his first goals ever against Real Madrid playing at their stadium. Even if it was just a lucky night, Torres will have the opportunity to play against one of the teams he loves to score against. Whenever Torres scores, either Atletico or Chelsea have not lost a match facing Los Blaugranas, drawing only two games. The 30-year old striker capped Chelsea's stunning draw against Pep Guardiola's team back in 2012, eliminating the Spanish team of the 2012 Champions League.

Which striker will be more decisive in their Copa del Rey matchup?