A full-strength side offered little resistance at Borussia Park on Wednesday as Bayern suffered a club-record defeat in the German Cup.
Salihamidzic described Bayern's performance as a 'collective black out' and demanded an improvement in east Berlin, where Union are unbeaten in their last 21 home league games.
"We want to give each other a short shake and step on the gas Saturday," fumed the Bayern sports director.
Union are the only Bundesliga team who did not lose to Bayern last season when both home and away league games ended in 1-1 draws.
Bayern can expect a tough time at Union's Alten Foersterei stadium, where they will need to tighten their defence after Dayot Upamecano and Lucas Hernandez looked vulnerable on Wednesday.
