Rangers last week signed Clint Hill, adding to their defensive strength in depth - but the centre-back is not a long term option.
Hill has signed just a one year deal, and turns 38 later this year, and it would not be a surprise to see them add another defender.
One opportunity which may be too good to turn down is the chance to bring back Kyle Bartley, who is likely to be made available by Swansea City this summer.
Sone Aluko - Rangers celebrates his goal with Kyle Bartley
Bartlley signed for Rangers on loan as a teenager from Arsenal, late in the 2010/11 season and then in 2011/12.
He caused a stir with a crunching tackle on Celtic's Scott Brown just two minutes into an Old Firm game, and quickly adapted to the club.
Rangers were demoted the following season, ending any chances they had of signing him permanently, and the former England youth international signed with Swansea City.
His time at the club has proved difficult, playing under a succession of different managers, and struggled for chances under current boss Alberto Paloschi.
Rangers' Kyle Bartley applauds the fans
It is a good opportunity for Bartley to move on this summer, having made only five Premier League appearances for the Swans last season.
With Rangers back in the Scottish Premiership, a deal would surely appeal to the 25-year-old, if current boss Mark Warburton decides the talented defender would be a worthy addition to his squad.