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Mangala, a £32m signing from Porto in 2014, has been serving as City's fourth choice centre-half this season behind Vincent Kompany, John Stones and Nicolas Otamendi. The Frenchman has been pushed further down that pecking order however after City wrapped up a deal to sign Athletic Bilbao's Aymeric Laporte after meeting the centre-half's €65m (£57m) release clause.
That arrival, which was confirmed by the club on Tuesday [30 January], is now set to trigger Mangala's departure with first-team opportunities under Pep Guardiola to dry up even further. Newcastle United were said to have made an approach for the 26-year-old earlier this week, but according to Sky Sports News, Everton are now close to agreeing a deal to bring the powerful defender to Goodison Park on an initial loan deal.
Mangala's desire to leave the runaway Premier League leaders stems from his concerns over making the France squad for next summer's World Cup.
He told Sky Sports News in November: "The World Cup is still on my mind. You have to be realistic, at the moment it's impossible for me to go to the World Cup.
"In two, three or four months' time, we'll see what's going to happen. The season is long; you never know what's going to happen but today it's complicated. I'm going to fight until the end and we'll see what happens."
Mangala has made 15 appearances in all competitions for City this season, filling in for Kompany and Stones while the two have been injured.
Sam Allardyce has made two first-team additions to his Toffees squad this month, bolstering his attacking options with Cenk Tosun and Theo Walcott arriving from Besiktas and Arsenal respectively.
Elsewhere, Davy Klaassen is expected to leave on loan before the transfer window closes after Everton confirmed the departure of Sandro Ramirez, who has returned to Spain to join Sevilla until the end of the season.