Sydney confirmed Papley had suffered a concussion in the knock, meaning the All-Australian forward will be required to follow the AFL's 12-day concussion protocol period.
The sideline stint will place Papley out of action and training until Friday, September 2 - what will likely be the second day of the opening week of finals.
The AFL are expected to schedule a Thursday night fixture among the four matches to start the post-season, with Papley to miss the match should Sydney be scheduled to open finals.
— Sydney Swans (@sydneyswans) August 21, 2022
A large enough win over the Saints will see the Swans clinch a top-two finish and home qualifying final, while a third-placed finish looms just as likely should they win by a smaller margin.
The AFL are expected to release the week one finals fixture shortly after the end of Round 23.