German newspaper Sport Bild were the first to report that the 2-1 defeat to Werder Bremen on Saturday would be the Dutchman's last in charge of the club.
The result saw Dortmund slip out of the top six for the time since Matchday 12 of the 2016/17 campaign and only served to increase the pressure on Bosz's job security as fans aired their discontent throughout the match.
"Honestly, this was a complete disgrace from us," Dortmund captain Marcel Schmelzer admitted after a performance that has once again drawn its fair share of criticism. "I have no explanation how this kind of performance can happen. I'm saying the same things every week. It doesn't help anything."
Leading up to the game, Bosz seemed unsettled as he was forced to answer questions regarding how a fire alarm going off at the team hotel would affect his side and whether rumours that his players had influenced his starting line-up decisions were true. The result did little to improve his mood after the final whistle.
"I think I'm the right man for the job," a disconsolate Bosz told Sky Sports Germany. "I'm responsible for what happens out on the pitch. The disappointment is clear to see and hard to deal with. But you'd have to ask them [the Borussia Dortmund board] as to whether they still have faith in me to do the job."
According to the German media, the answer to that question is a resolute no.
Dortmund travel to Mainz in midweek and play host to Hoffenheim at the Signal Iduna Park before closing out the year with a German Cup last 16 tie against Bayern Munich.