The Man City boss ideally wants a centre-bavk who would be eligible to play in the Champions League, and Maguire fits the bill.
City's hierarchy believe that a deal in the region of £30m could be struck, although reports suggest the two clubs are still afar off in the player's valuation.
City were originally prepared to wait until the summer in the belief Sanchez had set his heart on a move to Etihad Stadium and a reunion with former manager Pep Guardiola.
City are also considering buying a centre-back in the transfer window, with West Bromwich Albion's Jonny Evans remaining a leading option, although ironically they could face competition from Arsenal for the Northern Ireland worldwide.
Matt Le Tissier reacts to Virgil van Dijk's goal for Liverpool
Everton , who confirmed the sale of midfielder Ross Barkley to Chelsea in the hours leading up to the match, were also at full strength.
Arsenal's Shkodran Mustafi is reluctant to be drawn into a debate regarding the futures of "top class players" Alexis Sanchez and Mesut Ozil.
The 25-year-old was also being chased by Chelsea and Arsenal, but has made a decision to stay at Turf Moor.
Manchester City are said to be confident of landing the Arsenal man for as little as £25 million.
The Gunners forward has been linked with a potential January move over the past few months given his contract situation at Arsenal.
The injury to Gabriel Jesus is thought to have had an impact.
Arsenal are reportedly ready to allow Alexis Sanchez to leave during the January transfer window after deciding that they do not want to lose the forward on free transfer in the summer.