The Blues play host to the Hatters on Saturday (12.30pm kick-off) as Championship football returns to Fratton Park for the first time in 12 years.
However, the chances of Rob Edwards being able to welcome the Republic of Ireland defender to their ranks before then look remote, with the Bluebirds holding out for £10m for the centre-back.
Cardiff boss Erol Bulut confirmed the Welsh side have received an offer for the defender, who was not included in the Bluebirds’ match-day squad for last Saturday’s defeat at the hands of Sunderland. Yet they fall below their valuation of the player.
‘Yeah, I think (there is a bid). We are now on the level where everyone is talking about the transfer.’ Bulut told WalesOnline.
‘Interest is always there. Luton or other clubs. This is why he had so much interest. He is now a player of Cardiff City. He will continue in that way. If nothing comes we are pleased to have him here. It’s a free market. They can test. The player belongs to us, so we don’t have any rush for this. The value of the player is this. When the club gets this value then the club will go forward.’
Luton have had a relatively quiet transfer window following their return to the Championship from the Premier League, with just two signings on free transfers to date – Reuell Walters and Shandon Baptiste.