Williamson eyes ex-player
By Mark Buckingham
Last Updated: 01/01/70 1:00am
The Scotland international was signed by Williamson on a free transfer from Newcastle United during January's transfer window.
But he is available for nothing again in the summer and Williamson is believed to be keen to re-sign the centre half.
With Plymouth preparing for First Division football next season, Williamson is looking to bolster his squad after only recently taking over at Home Park.
Caldwell has already played in Division One this term while on loan at Derby County and Williamson is confident the 22-year-old would be an excellent addition to the ranks.
Another Hibs player under consideration as a potential summer signing is French defender Matthias Doumbe.
His deal also expires at the end of the season and Hibs have offered the stopper a take it or leave it extension.