The 25-year-old Germany international defender faces three weeks on the sidelines after suffering a muscle injury in Borussia Dortmund's pre-match training on Friday
Schmelzer has been ruled out for BVB's Champions League encounter against Marseille and the Bundesliga clash with Borussia Monchengladbach that follows it.
However, team doctor Markus Braun is optimistic that the Germany international could return for the league encounter against Hannover on October 19.
The 25-year-old has already made nine appearances in all competitions for Dortmund this season, scoring one goal in the process.
During BVB's 5-0 rout over Freiburg, manager Jurgen Klopp called on 21-year-old Erik Durm to fill the void left by Schmelzer's injury.