Alexis Sanchez changed his mind about signing a new contract with Arsenal after the Gunners were beaten 10-2 on aggregate by Bayern Munich in last season's UEFA Champions League, according to Matt Hughes of The Times.
Hughes noted how Sanchez "agreed the terms of a new deal at the club 12 months ago," with the forward and the Gunners "even understood to have shaken hands on the deal last December."
The U-turn came after Arsenal lost 5-1 in each leg of their last-16 tie against the Bundesliga giants, prompting Sanchez to make it clear he wanted to leave for Manchester City. He is expected to run down his contract and leave for free next summer.
When he does depart, the Chile international will join City on a deal worth £400,000 per week, per John Cross of the Daily Mirror. However, the Citizens may need to act faster if Ligue 1 side Paris Saint-Germain firm up their interest this winter.
Les Parisiens are planning a £25 million bid for Sanchez during the January transfer window, according to Tony Banks of the Daily Express. If PSG do make their move, City will counter with a midseason bid of their own, per the London Evening Standard's James Olley.
City's interest in Sanchez is no secret; the Manchester club tried to sign the versatile attacker for £60 million during the summer, per BBC Sport's David Ornstein. The connection between Sanchez and City boss Pep Guardiola, who signed the South American during his days at Barcelona, is also a key factor.
Guardiola has tried to swat away questions about his plans regarding Sanchez, although he hasn't always been successful in quieting the speculation.
Earlier in December, the 46-year-old passed up the chance to deny the rumours he will bid for the player in January: "Good question! That's why you're here (laughs). On the pitch you know. The transfer window is in winter time so I don't know. I don't know what we are going to do, because it's not...OK."
Guardiola may be content to leave the door open, but Arsenal manager Arsene Wenger has remained adamant Sanchez will stay. He recently assured fans both the South American and fellow contract rebel Mesut Ozil will see out their deals, per James Benge of the London Evening Standard.
It's a calculated gamble from Wenger since he risks losing both players for nothing at the end of the season. The Frenchman is also betting Sanchez will remain committed to the Arsenal cause in the meantime.
Sanchez's effort has been questioned by many this season, including Gunners legend Ian Wright, who accused the forward of "clocking off" during a recent appearance on BBC 5 live Sport.
While it's easy to criticise Sanchez, to do so overlooks the difference the gifted 29-year-old can still make. Even in a down season, the prolific No. 7 has found the net six times and provided three assists in all competitions.
Sanchez is one of the few world-class talents in Wenger's squad. While his boom-or-bust style of play is frustrating at times, particularly when his tricks and flicks don't come off, the Chilean also offers the magic the Gunners need in order to win trophies.
Since Arsenal remain in the thick of the race for a top-four finish in the Premier League, Sanchez has an important role to play. He'll also be a key figure in helping the club in the Carabao Cup semi-final, the UEFA Europa League round of 32 and the defence of the FA Cup.
There aren't many forwards on the market with Sanchez's ability, so Wenger is right to bank on his attacking talisman rather than cash in.