Tomiyasu has been struggling with a muscle issue since appearing at the World Cup with Japan and he missed the Gunners’ Boxing Day win over West Ham.
The right-back has since returned to training, though, and returns to Arsenal’s squad.
“He is getting closer and closer. He has been training with us, so he is available,” said Arsenal manager Mikel Arteta in his pre-match press conference.
Arsenal are without Emile Smith Rowe (groin), Gabriel Jesus (knee) and Reiss Nelson (hamstring).
Of those, Smith Rowe is the closest to making a return and should make his comeback early next month.
“He has made some big steps in the last week or so, took part in a few training sessions lately and is looking good,” said Arteta.
Zinchenko in for Kieran Tierney is the only change to the side that beat West Ham last time out.
Arsenal XI: Ramsdale, White, Saliba, Gabriel, Zinchenko, Partey, Xhaka, Odegaard, Saka, Martinelli, Nketiah.
Subs: Turner, Holding, Cedric, Vieira, Lokonga, Elneny, Marquinhos, Tierney, Tomiyasu.
Saturday 5.30pm GMT, Sky Sports
Venue: Amex Stadium
Referee: Anthony Taylor