Referee Felix Brych awarded a freak goal that should never have stood as Sami Hyypia's Bayer Leverkusen went to the top of the Bundesliga with a 2-1 win over Hoffenheim.
Stefan Kiessling's header for Bayer Leverkusen missed the target and the striker even held his head in frustration, but somehow the ball crept through the side-netting and Brych signalled a goal.
Leverkusen accepted the gift, that put them two goals ahead and on the way to a 2-1 victory, but it was certain to spark post-match controversy.
Sidney Sam had given Leverkusen a first-half lead, and Kiessling's bizarre goal meant Sven Schipplock's late reply was worthless to the hosts.
Sam struck in the 26th minute with a low shot from outside the penalty area beyond Koen Casteels.
The second goal is guaranteed a place in football history for being a refereeing blunder, and it remained to be seen whether Hoffenheim would file a complaint.
Kiessling rose to meet a corner delivered from the left by Gonzalo Castros and headed the ball into the side-netting. Implausibly, the ball managed to burst through a small hole in the net and rippled the inside of the goal.
Since the ball emerged as if it had crossed the line, the referee awarded the goal and Kiessling's initial dismay at his miss turned to a mixture of joy and embarrassment.
Several Hoffenheim substitutes raced behind the goal to examine the netting for themselves, calling the attention of the referee to a small hole where the ball had entered, but the official was then powerless to overrule his original decision.
He made amends to a certain extent by awarding a generous penalty when Roberto Firmino was fouled a foot outside the penalty area.
Firmino's spot-kick was saved and his rebound hit the post with Omer Toprak striking the rebound back against the woodwork in another dramatic turn of events.
Schipplock managed to head in a consolation, but it came too late to give the home side a chance to get back on level terms.