The Japanese right-back was forced off in the second half of Saturday's 2-1 win over Wolverhampton Wanderers, although Arteta was none the wiser about the nature or severity of his affliction after the game.
Nevertheless, the three-day turnaround means that Tomiyasu has emerged as a doubt for Tuesday, where all of Jurrien Timber (knee), Emile Smith Rowe (knee), Fabio Vieira (groin) and Thomas Partey (thigh) will be missing too.
Tomiyasu's injury is a cruel blow to a player who has reignited his Arsenal career this season, but thankfully for Arteta, he has a ready-made replacement in the form of Ben White, who should join an otherwise unchanged defensive setup.
Jakub Kiwior is an option to come in for Oleksandr Zinchenko, who was at fault for Matheus Cunha's goal at the weekend, but the Ukrainian ought to link arms with William Saliba and Gabriel Magalhaes in front of David Raya yet again.
As ever, Declan Rice and Martin Odegaard's spots in midfield are safe, but the third and final place in the trident is up for grabs, and an improving Kai Havertz may get the nod over Jorginho to start this one.
A recall for Havertz could push Leandro Trossard further up the field if Arteta decides that Gabriel Martinelli is in need of a break, but Gabriel Jesus and Bukayo Saka should reprise their roles in the final third after Eddie Nketiah's underwhelming cameo on Saturday.
Arsenal possible starting lineup: Raya; White, Saliba, Gabriel, Zinchenko; Odegaard, Rice, Havertz; Saka, Jesus, TrossardNo Data Analysis info