Borussia Monchengladbach forward Thorgan was thought to be heading to Bundesliga rivals Dortmund, but the clubs are yet to agree a fee.
Liverpol and Arsenal sense a chance to sign the younger brother of Eden, according to the Sun.
The 26-year-old is formerly of Chelsea's academy but never made a first-team appearance and has blossomed in the Bundesliga since leaving Stamford Bridge.
However, a return to England isn't off the cards as two of the Premier League's top sides enter the race for his signature.
Liverpool are looking to bolster their attack and manager Jurgen Klopp could frustrate his former club with a move for the Belgium international.
Unai Emery, on the other hand, is in desperate need of a winger and will reportedly ask Arsenal's negotiators to get a deal done if possible.
7 brilliant teams pulled apart before they could fulfil their potential
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