Filling, 17, made his Allsvenskan debut last season, scoring twice in nine appearances, and has featured five times in the current campaign. He turned 17 in November, meaning no English club can sign him until he turns 18 — a rule that leaves Newcastle United exposed to clubs across continental Europe who face no such restriction.
The Daily Mail reported in February that Newcastle's scouts are admirers of Filling, comparing him to Alexander Isak — another AIK forward who left for Borussia Dortmund at 17 before going on to reach the very highest level.
Sporting director Ross Wilson and head of football strategy Jack Ross are understood to be exploring a multi-club model, partly to circumvent the age restriction problem. Filling is exactly the kind of player that model is designed to protect.
Sportbladet reports that Swansea City, currently in the Championship, offered around 25 million Swedish kronor — roughly £2million — for Filling several weeks ago. AIK turned it down.
Manchester United, Aston Villa, Borussia Dortmund, RB Leipzig, VfB Stuttgart and Sturm Graz were all linked during the January window. Sturm pushed hardest, submitting multiple offers, all of which were rejected.
Filling is contracted to AIK until 2028.
Newcastle's admiration is clear. Whether they can find a route to signing him before a European club does is the more difficult question, and the clock is already ticking.