Winnall has hit an impressive 11 goals in 20 appearances in the Championship for the Tykes this season but he's out of contract in the summer and has so far refused to enter into talks over a new deal, making it increasingly likely he will move on this month.
Barnsley obviously want to keep the forward but also do not want to lose him for nothing in the summer so reports claim clubs could secure his services for as little as £500,000 in January.
The situation has alerted the Canaries, who are ready to rival the Owls in a potential deal.
The 25-year-old came through the ranks at Wolves before several loan spells and ended up at Scunthorpe before joining Barnsley in summer 2014.
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