Despite agreeing the basic framework of a move for Gyökeres weeks ago, Arsenal and Sporting found themselves butting heads over the nature of the add-ons proposed by the Gunners, which invited pressure of a potential hijack from long-term admirers Manchester United.

Arsenal are putting the finishing touches on a deal to sign Viktor Gyokeres after a key breakthrough in negotiations with Sporting. The Gunners have struck a deal worth £54.8million plus £8.6m in potential add-ons but the deal was being held up due to issues over the nature of the add-ons.