The Bundesliga club have revealed that Switzerland international Xhaka suffered a ligament and capsule tear in his right ankle late on in Sunday's goalless draw with the champions.
Coach Lucien Favre had already made three substitutions, so Xhaka returned to the field after receiving treatment and limped through the closing stages.
Gladbach stated on Monday that Xhaka is set to miss "upcoming games", but it is not clear how long the 22-year-old will be sidelined for.
Xhaka has been an ever-present for Gladbach this season, featuring in all 15 competitive games for Favre's side.
Gladbach, now third in the Bundesliga, face a trip to Eintracht Frankfurt in the DFB Pokal on Wednesday ahead of a home league game against second-placed Hoffenheim at the weekend.
