Tuchel had missed Chelsea’s past two games, including Wednesday’s 1-0 win over Al Hilal, after contracting the virus last week.
He had been isolating at home in line with government protocols, before eventually testing negative and receiving clearance to travel and join up with the squad.
Assistant coach Zsolt Low, who has been in temporary charge along with Arno Michels, said the staff had been in constant communication with Tuchel despite his absence in the UAE.
Asked earlier if Tuchel’s presence on Saturday would make a difference, midfielder Jorginho said: “Of course it gives you more, there’s more energy in the changing room.
“It’ll be really important for us if he could be here.”