Who plays alongside Shad Ogie in central defence this weekend is the big question for the Gills as they head to Doncaster. With Gillingham captain Max Ehmer suspended for a match and other obvious options on the treatment table, it’s left boss Mark Bonner with plenty to think about. More: Gillingham team news for Doncaster trip On Tuesday night Ehmer was free to play in the EFL Trophy – following his dismissal last weekend against Chesterfield – and partnered Alex Giles at the back. Giles, 19, played in the League Cup with a tough game at Swansea City and has no Football League experience. Las…