The Daily Star Sunday says Argentina’s Otamendi, valued at £25m, is the new name in the frame for City.
City sent International Recruitment Manager Rob Newman to assess Otamendi, 25, in Porto’s 3-1 win against Sporting Lisbon last Sunday.
Blues boss Manuel Pellegrini is said to be concerned about skipper and centre back Vincent Kompany’s ongoing injury issues.
City have told Pellegrini they’ll back him in the January transfer window if he wants to make a significant signing.
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