Thomas, who recently signed his first professional deal on his 17th birthday, was on the bench for City's first game at Reading yesterday, missing City U18's 1-1 draw at MK Dons.
However, City first team manager Aidy Boothroyd has given Thomas permission to play in the game which kicks off at Roots Hall at 7.30pm.
Admission is £3 for adults and £1 for concessions.
Picture copyright of Covsupport News Service. Credit CNS/RK