Arthur Melo
Barcelona are said to have watched Arthur Melo during the first leg of Gremio's Copa Libertadores final against Lanus Buda Mendes/Getty Images

Barcelona are stepping up their pursuit of Arthur Melo, according to reports, with Manchester United and Chelsea also believed to be keeping a watchful eye on the progress of Gremio's sought-after creative midfielder.

Arthur has earned favourable comparisons to Andres Iniesta since bursting onto the scene in Porto Alegre and was rewarded for his impressive club form in September by being called up to the senior Brazil squad for a final pair of 2018 World Cup qualifiers against Bolivia and Chile.

According to Goal, Barcelona have been tracking the 21-year-old - full name Arthur Henrique Ramos de Oliveira Melo - since the start of the season and dispatched globetrotting technical director Robert Fernandez to South America to watch him in action during the first leg of Gremio's 2017 Copa Libertadores final against Argentine outfit Lanus last week.

The same publication report that Fernandez also attempted to develop a more in-depth knowledge of the player, who could reportedly be available for a fee in the €15m-20m range in January despite the fact that a recent four-year contract extension signed at Gremio contains a (£44.7m, $59.4m) release clause worth €50m.

Fernandez is currently said to be in Argentina, where he watched the likes of young quartet Marcelo Saracchi, Alexander Barboza, Gonzalo Montiel and Nico de la Cruz in action during River Plate's 3-1 home defeat by Newell's Old Boys over the weekend. It could be that he remains in the Buenos Aires area for the second leg of the final clash between Lanus and Gremio, which takes place on Wednesday night (29 November).

Barcelona boss Ernesto Valverde recently admitted that he would be open to further signings in the New Year as his unbeaten side seek to preserve and stretch their four-point lead at the La Liga summit, with midfield depth expected to be a key area of concentration.

The Blaugrana look likely to revive their long-running pursuit of Philippe Coutinho when the market re-opens for business, while Arsenal contract rebel Mesut Ozil and Lyon's Nabil Fekir have both emerged as affordable alternatives to the Liverpool playmaker.

However, Valverde does not look likely to strengthen his centre-back ranks with a player such as Palmeiras' Yerry Mina unless one of his current defenders departs or suffers an injury between now and January.

Barcelona are far from the only club interested in Arthur, with The Mail reporting earlier in November that Jose Mourinho and United were also keeping tabs along with Chelsea and Atletico Madrid.