Champions Bayern Munich moved back top of the Bundesliga ahead of RB Leipzig on goal difference despite having to come from a goal behind for the fifth consecutive league game as they rescued a point at Union Berlin on Saturday.
Union stunned the visitors in the fourth minute with Grischa Promel's glancing header from a corner.
It was a familiar scenario for the Bavarians, whose 17 conceded goals equals their worst defensive showing after 11 league games.
The hosts were the far better side and twice came close with Taiwo Awoniyi, who forced a sensational save from Manuel Neuer in the opening minute and beat the keeper but fired wide midway through the first half.
The Bavarians struggled to find their rhythm in the opening period while also leaving big gaps in the defence but after the break, as Union fans outside the stadium chanted and lit fireworks, the visitors connected a bit better.
Bundesliga top scorer Robert Lewandowski rescued a point in the 67th minute, making no mistake after an excellent dribble and cut-back by Kingsley Coman for the Pole's 13th goal of the campaign on his 200th appearance for the club.
Union goalkeeper Andreas Luthe made the save of the day in stoppage time, palming away a Leroy Sane header from point-blank range.
Bayern, who have won only one of their last four league games, are level on 24 points with Leipzig, who beat Werder Bremen 2-0 earlier on Saturday. Bayer Leverkusen, on 22 points, can take over top spot with victory over Hoffenheim on Sunday.