By Paul Clennam and Sam Lee
The Argentina centre-back has agreed personal terms with City after Valencia agreed to a deal which, at €45m going by current exchange rates, is short of the €50m they had been holding out for all summer.
Details of City's intent to seal a deal for the 27-year-old emerged during Sunday's 3-0 victory against Chelsea, with Eliaquim Mangala purported to be heading to Mestalla on loan.
But after the Premier League leaders made it clear the Frenchman, himself signed for £41m just last summer, would not be going anywhere, a straight cash deal was agreed despite Jason Denayer and Marcos Lopes being touted as alternative options during negotiations.
Confusion shrouded proceedings on Tuesday morning when it was reported in Spain that Otamendi was back in training at Valencia, while several British outlets insisted he was still in Manchester having travelled to England alongside agent Jorge Mendes on Monday night.
But with Otamendi now at Wilmslow, the same hospital where Fabian Delph and Raheem Sterling have been through their paces, the big-money move will be soon confirmed.
Official confirmation of the deal could be delayed slightly, however, given that Valencia are preparing for their Champions League qualifier against Monaco on Wednesday evening.