The England captain, Bayern's leading scorer this season, was ruled out of the match at the Allianz Arena after failing to recover in time. Speaking at his pre-match press conference, Kompany explained that Kane was close to being available but ultimately ran out of time.
"Hiroki Ito is out, Alphonso Davies is out and Harry Kane is out. He got a knock on his calf and hasn't recovered yet," Kompany said.
"It's just a knock, it's nothing serious for the time being, but we're missing a day maybe for him to be involved. We're pretty relaxed. Of course we would have liked Harry to be involved, but these things happen."
Kane has been central to Bayern's attacking success since joining from Tottenham Hotspur, consistently delivering goals in the Bundesliga and Europe. His absence against Gladbach removes a key focal point from the champions' attack, but Kompany insisted the squad still has players ready to step up.
Kane has scored 45 goals in 37 appearances for FC Bayern Munich across all competitions so far in the 2025–26 season.
The Belgian manager believes Kane's absence could provide an opportunity for other attacking players to make their mark.
"The lads who are involved tomorrow against Gladbach are really looking forward to it," Kompany said.
"If Harry isn't involved, some of the lads are hoping they can get their moment. We as the staff are also looking forward to being part of that."
There was better news for Bayern in goal, with Kompany confirming that captain Manuel Neuer had recovered from injury and was ready to start.
Bayern will be keen to manage Kane carefully, with a major European fixture approaching. The German champions are scheduled to face Atalanta in the first leg of their UEFA Champions League round of 16 tie on Tuesday, and the club will hope their star striker is fully fit for that crucial encounter.
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