Porto’s Otamendi is also being tracked by Manchester City.
Chelsea, Manchester City and Manchester United are on alert as FC Porto defender Nicolas Otamendi remains open to a move to the Premier League, according to the Daily Express.
The Argentina international was set to make a loan switch to Valencia, but the Spanish side could not afford Porto’s demands for the player.
It means that Otamendi is left in limbo and would be ready to make a switch to England before the January transfer window closes on Friday.
The Blues previously kept tabs on the 25-year-old as they looked to strengthen their back four, although Gary Cahill and John Terrry have formed a solid partnership in central defence since then.
City meanwhile are looking for a long-term replacement for Joleon Lescott and were linked with a move for Otamendi and the South American’s team-mate Eliaquim Mangala.
Yet things have gone quiet with the two clubs since and it’s the Red Devils that have stepped up the chase, with manager David Moyes looking to the future as veterans Rio Ferdinand and Nemanja Vidic approach the end of their respective careers.
However, the Scot will face strong competition as AC Milan, AS Monaco and Barcelona are all thought to also be interested in the Argentine.
Otamendi is keen to leave the Portuguese champions for a more high profile side in order to try and cement a place in the national team ahead of the 2014 World Cup.
The Argentinian has been with Porto since the summer of 2010 and has since played 122 times for the club and won the Primeira Liga three times and the Europa League in 2011.
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