Arthur Abraham was given until 3.40pm (UK BST) to make the weight after shockingly weighing over by 1lb and 13oz.
The former two-weight world champion originally came in at 12 st 1lb and 5oz. Bemused, Abraham demanded the scales to be moved to the floor as he looked on in disbelief.
IBO champion Chris Eubank Jr weighed within the limit at 11st 13lbs and 3oz.
A short time later, the German veteran was able to drop the excess poundage to stay on course for the IBO title by scaling 11 st 13lb and 10oz.
The pair collide at the SSE Arena in London on Saturday night, with the winner then moving on to the coveted World Boxing Super Series tournament.
In the draw last week, Chris Eubank Snr chose highly-rated contender Avni Yildrim as the opponent.
The quarter-final will take place in September or October of this year.
Joe Hewlett is lead writer for World Boxing News. Follow Joe on Twitter @Hewlett95