Borussia Dortmund face a deepening injury crisis in the build-up to the new Bundesliga season with captain Marcel Schmelzer the latest to be sidelined.

The full-back suffered ligament damage in an ankle in Monday's training session in Guangzhou, a problem that was only fully diagnosed after the 29 year old's return to Germany.

Schmelzer is expected to be out for up to a month, meaning he could miss his club's return to Bundesliga action at Wolfsburg on 19 August.

With Julian Weigl (ankle), Marco Reus (knee) and Raphael Guerreiro (foot) already in the treatment room, new coach Peter Bosz's plans for Matchday 1 have already required some reworking.

The former Ajax boss, who took over from Thomas Tuchel this summer, has options though.

"We have Erik Durm and Felix Passlack who can play in this position, there's also Dan-Axel Zagadou," BVB CEO Hans-Joachim Watzke explained.

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