The Cameroonian midfielder only left the Gunners in 2012 to join the Spanish heavyweights, but he’s endured a disastrous two years at the Camp Nou.
And now with new chief Luis Enrique having brought in a host of players over the summer, Song is free to leave.
A loan switch has been mooted, while talk suggests that offers of £10m will be enough to lure the deep-lying playmaker away from La Liga.
Among a range of sides interested are Arsenal, with Arsene Wenger tempted by his former star.
The Frenchman is keen to bring in options for both central midfield and centre-back, which are both positions the African ace can fill.
Talks have not yet been opened but Song’s future could be resolved over the weekend, with the transfer deadline ticking ever closer.
Tottenham have also been linked with the 26-year-old, while Liverpool are rumoured to be interested.