One of Norwich City's reported defensive targets from last summer could be available on a free transfer at the end of this season.

Union Berlin centre-back Toni Leistner was strongly linked with City as reports in the German media suggested a deal worth around £3.5million for the defender was possible.

While that transfer never happened, the 27-year-old is now in the final six months of his contract and free to speak to other clubs – although a promotion clause could complicate matters.

Union have a 12-month extension in Leistner's contract which would be activated by promotion but currently sit eighth in Bundesliga II, five points adrift of Holstein Kiel in the play-off place and 10 behind the top two, who go up automatically.

This has led to Cologne newspaper the Express linking struggling Bundesliga side FC Cologne with a move for Leistner, as it looks likely they will drop into the second tier.

Cologne's head of football, Frank Aehlig, told the Express: 'He has shown many years of good performance in the second league and is a free transfer during the summer. It is not only us who know that. We have not had any discussions.'

Liga-Zwei.de has suggested a move to England could still be an option as well, following City's interest last summer, with Leistner having made 18 appearances for Union so far this season.

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Whether the Canaries' German head coach Daniel Farke will still be keen on Leistner is likely to depend on the futures of Timm Klose, Marcel Franke and Russell Martin though.

City already have centre-backs Grant Hanley, Christoph Zimmermann, Sean Raggett and Franke on long-term deals but Switzerland international Klose will have 12 months left of his contract this summer and is still one of the squad's highest earners.

Franke has returned to the German second tier on loan with Dynamo Dresden for the second half of the season having struggled to settle after his summer switch from Greuter Furth and long-serving Martin is also due to return from a loan at Rangers, when he will have a year left on his contract.