Dortmund have now won just one of their last five league matches and are in seventh place on 12 points, two off leaders Bayern Munich.
Borussia Dortmund twice squandered the lead and conceded a 90th-minute own goal from Manuel Akanji to draw 2-2 against Freiburg on Saturday for their third consecutive league draw.
The Ruhr valley club, who beat Slavia Prague in the Champions League in midweek, have now won just one of their last five league matches and are in seventh place on 12 points, two off leaders Bayern Munich.
Axel Witsel's sensational volley from a corner put them in the driving seat but Freiburg levelled through Gian-Luca Waldschmidt after a fine combination from the hosts left the Dortmund defence standing.
Dortmund, who also wasted leads in their previous two league games and have been fending off questions about their winning mentality, thought they had done enough when Achraf Hakimi put them ahead again in the 67th. Defender Hakimi had also scored both goals in Prague on Wednesday.
However, the own goal by Akanji, who flicked a cutback into his own net, forced them to settle for a point once more.
"We are just not defending well enough in the end," said Dortmund captain Marco Reus. "Obviously it is bitter to concede an equaliser so late in the game.
"We did not play well in the second half but we just have to manage at some point to carry our lead over the line. Clearly we are missing two points."
Bayern are top on 14 despite a shock 2-1 home loss to Hoffenheim, and are ahead on goal difference of Freiburg as well as RB Leipzig and Bayer Leverkusen, who drew 1-1.