The playmaker was spotted on crutches following last weekend's victory over Manchester United, although he told the press that it was only a precautionary measure.
Nevertheless, Maddison was supposedly sent for scans on that apparent foot problem earlier this week, and Postecoglou will be expected to provide an update at his pre-game press conference.
In addition to Maddison, Spurs will definitely cope without the quartet of Bryan Gil (groin), Rodrigo Bentancur (knee), Ryan Sessegnon (hamstring) and Alfie Whiteman (ankle), all of whom are recovering from surgery.
As Hugo Lloris continues to search for an exit route, Guglielmo Vicario will hope to replicate last weekend's strong showing against the Red Devils, and the same can be said for Pedro Porro and Destiny Udogie out wide.
Cristian Romero also made a rapid recovery from a bang to the head to excel alongside Micky van de Ven, while Yves Bissouma will no doubt continue in the engine room after being given a new lease of life under Postecoglou.
Similarly, Pape Sarr's maiden Spurs goal capped off a man-of-the-match display against Man United, and assuming Maddison is fit enough, he will join the former Metz man and Bissouma in a formidable midfield.
Dejan Kulusevski, Richarlison and new skipper Son Heung-min are yet to set the world alight in Spurs colours this season, but none of them should be in any danger of losing their spots this weekend.
Tottenham Hotspur possible starting lineup: Vicario; Porro, Romero, Van de Ven, Udogie; Maddison, Bissouma, Sarr; Kulusevski, Richarlison, Son