Bayern Munich could end the weekend 10 points off the top of the Bundesliga after dropping points against Freiburg.
Christian Gunter fired the mid-table hosts into a lead with a fine 20-yard strike.
Bayern thought they had turned it round through Mathys Tel's excellent curling effort and Jamal Musiala's placed shot after a solo run.
But Lucas Holer struck an 87th-minute volley to snatch a point for the hosts.
"We played completely without structure," said Bayern coach Thomas Tuchel on his side's first-half performance. "We were not disciplined. We were not in our positions, we lost possession going forward and allowed them to counter-attack.
"It wasn't a matter of will, we played recklessly for the first half hour.
"We did things that we've never trained, that we've never spoken about. We played like it was the 85th minute and we were a goal down."
Bayern are now seven points behind unbeaten leaders Bayer Leverkusen, who visit Cologne in their game in hand on Sunday.
It could spell the end of the Munich outfit's decade of total dominance in German football. They have won a record 11 consecutive Bundesliga titles.
Their poor season has already led to the news Tuchel will leave at the end of the season.
If Bayern fail to beat Lazio on Tuesday in the Champions League last-16 second leg - they lost the first tie 1-0 in Rome - they are likely to end the season without any silverware.
It was a frustrating night for England striker Harry Kane, who missed several chances for Bayern and failed to build on his run of three goals in two games.
Source: BBC