The 23-year-old Porto defender was seen entering The Bridgewater Hospital in Manchester's Moss Side to undergo routine physical examinations ahead of his switch to the Etihad.
On Friday, Goal reported that the Premier League champion had made a breakthrough in talks with Porto over a deal for the France international, having given him until Sunday to accept the offer.
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Mangala arrived at The Bridgewater Hospital in Manchester's Moss Side a day later to complete a medical as he prepares to put pen to paper on a long-term deal which will earn him approximately €113,000-a-week.
The 23-year-old, who was part of the France squad at this summer's World Cup in Brazil, will go on a short holiday before joining up with the rest of the City squad for preseason training.
The deal brings an end to a long pursuit for the English club, which came close to signing Mangala in January but was ultimately frustrated by Porto's unwillingness to negotiate on a valuation.
Manuel Pellegrini has been searching for an elite defender to partner Vincent Kompany for some time, with Martin Demichelis and Joleon Lescott criticized for their performances last season and Matija Nastasic struggling for fitness.
Mangala has established himself as one of the most coveted center backs in European football during three seasons at Porto, though he has yet to earn a regular place in France manager Didier Deschamps starting XI.