The Dortmund boss didn't sleep well after the home loss to Red Bull Salzburg but now must refocus his team against Eintracht Frankfurt this weekend
Peter Stoger admitted Borussia Dortmund's nightmare display against Red Bull Salzburg left him struggling to sleep.
The Bundesliga club slipped to a 2-1 home defeat in the first leg of their last-16 Europa League tie on Thursday, leaving them with a mountain to climb when they travel to Austria for the return fixture next week.
Valon Berisha scored twice for the visitors and while Andre Schurrle bundled in a goal to halve the deficit, Dortmund slipped to their first defeat in 2018.