Here was the reason
According to Flick, Davies “had problems in the last two training sessions” and thus wasn’t deemed fit to play. Since Bayern went into the half-time break with a comfortable 4-0 lead, the Canadian sat on the bench throughout the match and was given extra time to regain full fitness for the Supercup. “He got the green light from the medical department for 45 minutes. We didn’t want to take any risk, however, and now have a little time for Thursday,” Flick said in his post-game interview.