Khumalo and Gerken in first-half action for Town
The 26-year-old Tottenham defender has trained with Blues this week and the White Hart Lane club have given him permission to play at Broadfield Stadium.
Fellow trialist Dean Gerken starts in goal for Blues after playing the second-half of the 2-0 win over Shelbourne on Saturday.
Academy scholar Kyle Hammond starts at right-back while Town fans will get a first glimpse of new signing Paul Anderson, who joins his former Bristol City team-mate Cole Skuse in midfield.
Town will field two different sides in each half, with the starting line-up: Gerken, Hammond, Mings, Smith, Khumalo, Skuse, Anderson, Hyam, Carson, Chopra, Murphy.
Former Town striker Billy Clarke starts for Crawley but Andy Drury is not included in their squad.