Sergio Aguero has had a massive impact on Manchester City since joining the club in June 2011. Two Premier League titles and 75 goals in just 122 games have helped transform the Citizens into one of the strongest teams in Europe. Can he now have the same effect with Argentina in the World Cup?
There is no doubt that the 26-year-old forward is in the best form of his career. In 2010, El Kun was still learning his trade. Though he was taken to that year's World Cup by coach (and then father-in-law) Diego Maradona and made a positive impact, it was all a little too soon for the star.
Four years on, Aguero is a more mature, stronger and, to put it simply, better player than he was in South Africa. English football has helped him build up his physical ability without losing a shred of natural talent, which has helped him to consolidate his place in the Argentina squad.
It has not always been easy for the ex-Independiente and Atletico Madrid prodigy. Aguero had to wait his turn behind forwards of the calibre of Carlos Tevez and Gonzalo Higuain under Maradona and successor Sergio Batista, which limited his minutes on the pitch.
He could be a very effective substitute—evidenced by his goal off the bench against Bolivia to save the Albiceleste from a Copa America defeat in 2011—but he faced an uphill task to break into the starting line-up. As with so many other players in the Argentina team, however, Aguero was revitalised with the arrival of Alejandro Sabella to the job.
Having proved his worth off the bench to secure a comeback qualifying victory away to Colombia, El Kun has rarely been out of the team since. The coach accommodated him in an attacking 4-3-3 formation, playing alongside Higuain and captain Lionel Messi in a set-up that makes opposition defences tremble in their boots.
Aguero's role in that fearsome trident is not the same as the one he carries out in England. The burden of scoring is shifted off his shoulders, with La Pulga and Pipita smashing the team to victory from the front. The pair scored 19 between them in Argentina's triumphant qualifying campaign, while Aguero trailed behind with a comparatively modest five.
But that statistic alone vastly understates his importance to the team. Aguero roams across the pitch in international colours, playing as a foil for the two hitmen. It is El Kun that drags players out of position so that Higuain can punch holes in the box. The Manchester City man drops deep to combine with the brilliant Di Maria on the counter-attack before haring forward to provide extra men in the final third.
He plays an entirely unselfish game, opening up the field for others with his creativity and vision.
In basketball terms, Aguero forms part of the Argentine "Big Three" alongside Di Maria and the captain. It is that trio's responsibility to galvanise their team-mates forward, create openings and rapidly turn defence into attack. Higuain will be there to fire home, but it is those behind him who will be in charge of providing the bullets.
The Albiceleste's class of 2005 is ready for glory. Five of the expected first team won the Under-20 World Cup of that year, with Di Maria and Romero joining Aguero two years later as he lifted a second youth title. The team know each other inside out, providing a cohesion and coherency that is often overlooked by observers.
Aguero has been playing with these men for years and knows exactly what makes them tick. If Argentina are to take their third World Cup, his contribution will be just as, if not more, vital than those of the many stars who surround him in the team.
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