The summer always generates plenty of interest among Celtic supporters regarding potential additions at Parkhead. With the window only a week away from officially opening for business, transfer speculation is already rife as Brendan Rodgers looks to add quality to his squad. Although there is no explicit admiration to speak of, plenty of discussion among fans has emerged following the release of Premier League clubs’ retained lists earlier this week. Several recognisable names are now on the market for free, including some individuals who have previously been linked with a switch to the Hoops….