The Kent team, one of only three teams below City, come to Ninian Park on Saturday week for a relegation "6 pointer"
Hessenthaler stepped down as manager but is still available as a player. His assistant, John Gorman, has taken temporary control.
When the Gills visit Cardiff John Robinson will not play for them. That was agreed when he moved from Cardiff last month. The 33 year old has been involved in 4 matches for Gillingham since his move. All were lost.