Wigan Athletic, Birmingham City and Coventry City are all plotting to sign Sunderland defender Tom Flanagan on a free transfer this summer, Football Insider understands.

The 28-year-old, whose current contract runs out at the end of the month, has been offered a new deal by the Black Cats but is yet to pen to paper.

A recruitment source told Football Insider that League One winners Coventry have joined Championship sides Wigan and Birmingham in the hunt to sign the centre-back for nothing.

Sunderland are set to spend another season in League One after seeing their play-off hopes extinguished by the immediate curtailment of the season.

Flanagan, a one-cap Northern Ireland international, finished the campaign as a mainstay for Phil Parkinson with eight successive starts at the heart of the defence.

The north east giants want to keep the former Burton Albion star at the Stadium of Light but they have been left sweating over his future with their contract offer left unsigned.

Coventry, who finished top of the table in League One, are hoping to add Flanagan to their ranks as they prepare for a return to the Championship next season.

As revealed by Football Insider earlier this month, the Sky Blues could lose first-team mainstay Michael Rose this summer with Leeds United setting their sights on the 24-year-old.

Meanwhile, Birmingham and Wigan, who sit 16th and 17th in the Championship respectively, are also keen on handing the centre-back a move back up the divisions.

Flanagan has a total of 57 second-tier appearances under his belt after his time at Burton.

In other Sunderland news, it can be REVEALED that Rangers have set their sights on signing a first-team ace from the Black Cats.

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