ESPN FC's Mark Lovell reported Die Roten are ready to head back in for Sanchez after star striker Robert Lewandowski complained of the workload he's under at the Allianz Arena:
Bayern have been hamstrung by recent injuries to Lewandowski and Thomas Muller, who usually deputises in the central striker role if the former is unavailable, but the list of alternatives ends after that pair.
It's no secret Sanchez looks likely to leave the Emirates Stadium in 2018, with his contract set to expire at the end of this season, and former Gunners defender Mikael Silvestre recently bemoaned the contract situation, via Goal:
Lewandowski and Muller both missed Tuesday's 2-1 UEFA Champions League win over Celtic, where the Germans looked considerably less lethal in attack, despite securing their place in the competition's round of 16.
Lovell also provided quotes from Bayern sporting director Hasan Salihamidzic, who spoke to Sky Germany before that clash and said of a new forward recruit: "It's got to be someone who can improve the team but still knows that Lewandowski is first choice."
Manchester City were the club most closely linked with Sanchez in the summer, but City refused to let Raheem Sterling move in the opposite direction, meaning a deadline-day deal couldn't be completed, per Sky Sports.
The Citizens will be glad they opted to hang on to the Englishman, too, as he's displayed superb form and was critical in the recent Champions League win over Napoli, per Simon Bajkowski of the Manchester Evening News:
Sanchez would be free to leave for any destination at the end of June 2018, and while City can't officially talk to the player until then, Bayern would be free to get a pre-contract agreement in place as of January.
Missing out on a summer switch doesn't appear to have hurt Sanchez much, however, and football.London reported how he was preoccupied during Arsenal's UEFA Europa League clash with Red Star Belgrade on Thursday:
There's also the pressing matter for Bayern to find eventual successors to Franck Ribery and Arjen Robben, their long-time wing servants who will turn 35 and 34, respectively, before the end of the current campaign.
Sanchez would make for a very decent replacement in regards to those two ageing figures, and Bayern may look likely to present Arsenal with another headache come the winter transfer window.