According to the Mirror's John Cross, Sanchez has been included in the squad for the match after training on Tuesday, with manager Arsene Wenger sending the message he will not consider any bids for the Chile international prior to kick-off.
City are said to have made an enquiry for the forward and will test Arsenal's resolve with a £20 million bid, though the Gunners value him at £10 million more despite his contract expiring in six months.
Speculation City might attempt to sign Sanchez in January—rather than recruit him for free in the summer—has intensified following Gabriel Jesus' injury, per football writer James McNicholas:
Per Goal's Sam Lee, Sky Blues boss Pep Guardiola has not been willing to discuss his team's interest in him:
City already have a great deal of firepower with the likes of Jesus, Sergio Aguero, Raheem Sterling and Leroy Sane competing for places—with David Silva, Kevin De Bruyne and Bernardo Silva doing the same alongside them—all of whom would command a starting berth almost anywhere else.
Sanchez's acquisition would enhance that further as they compete for multiple trophies and make a slip-up in the Premier League, which they lead by 15 points, even less likely to occur.
The 29-year-old has fallen below his high standard of play this season, but he has been an exceptional player for the Gunners throughout his time with the club, per Squawka Football:
A switch to City would likely reignite his form, so it would not be surprising if his disappointing campaign is of little concern at the Etihad Stadium.
Arsenal have two key clashes against Chelsea in the Carabao Cup semi-finals this month, though, and despite his mixed form this year, their best chance of overcoming the Blues is with Sanchez in the team.
That Sanchez will feature is by no means a guarantee he'll remain an Arsenal player come February, but the Gunners are at least hoping to get as much as they can from him before he departs.