Cowley made a late-window move to bring in the Scot from the League One leaders, but Millers boss Paul Warne wasn’t prepared to do business and weaken a squad on a Championship charge.
Now the Pompey head coach is keeping tabs on the former Celtic trainee’s situation, with a view to rekindling a bid going forward.
Lindsay is a popular figure among the Rotherham support, making 93 appearances and scoring five goals since moving to the New York Stadium from Ross County in 2019.
He was viewed as one of his side’s main players in the Championship last term, but has found playing time harder to come by this season starting one of Rotherham’s past nine league games.
A shoulder injury has been causing him problems of late, while his side have a powerful midfield trio in place in the shape of Dan Barlaser, Ollie Rathbone and Ben Wiles.
Lindsay’s current contract comes to a close this summer, but the Millers hold an option to extend his stay at his club.
It’s probable they would secure his future to protect their asset, even if he is likely to move on going forward.
Cowley faces another busy summer of squad reshaping, with 12 of his players out of contract - although there are options on the vast majority of those men.
Although the middle of the park is an area where his side are well stocked in terms of quality, the Pompey boss is still likely to want to bolster his squad in that area.
Joe Morrell and Ryan Tunnicliffe have their futures tied down, while Louis Thompson, Shaun Williams and Jay Mingi all see their agreements come to a close this summer.
Lewis Wing was another option considered at the end in January, but he eventually moved to Wycombe from Middlesbrough on an initial deal which runs until the end of the season.
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