A five-match unbeaten run has powered Union to safety, and the in-form hosts needed just five minutes to break the deadlock.
In the right place at the right time, Andrej Ilic couldn’t miss from only a few yards out as Jeff Chabot’s mistimed clearance left the Serbian with the simple task of scoring for the second time in four matches.
The hosts’ lead should have lasted only six minutes as Ermedin Demirovic’s run beat the offside trap to get in on goal, yet he inexplicably misfired his effort wide.
Demirovic’s contender for miss of the season took just eight minutes to haunt Die Schwaben, as Leopold Querfeld’s flick-on allowed Diogo Leite to head home his first-ever Bundesliga goal.
Stuttgart were stunned, but regained their composure and restored parity by scoring twice in a devastating six-minute spell. First, Deniz Undav marked his first start in over a month by halving the deficit with a screamer from range, before Enzo Millot produced an exquisite equaliser with a strike of arguably even better quality from a similar distance.
Long-range efforts were clearly on the menu, with Querfeld letting loose an unstoppable strike that flew straight into the top corner to restore Union’s lead.
Extraordinarily, there was still time for three more goals in a blockbuster first half.
Chabot made it 3-3 by redirecting Angelo Stiller’s inviting delivery beyond Frederik Ronnow, before Chris Fuhrich gave Stuttgart the outright lead with a well-executed finish.
However, deep into stoppage time, Ilic doubled his personal tally to bring Union level by expertly finishing once again from a similar position to his first goal.
The eight goals scored before half-time was an all-time Bundesliga record, so perhaps it wasn’t a surprise to see the contest struggle to match the same level of entertainment following the restart.
Benedict Hollerbach looked to follow in the footsteps of the Stuttgart scores by unleashing from distance, but he fired over before Demirovic forced Ronnow into a fine save at the other end.
Ultimately, that would prove to be the last noteworthy effort of a second half that offered precious little entertainment, especially in comparison to what came before.
The draw guarantees Union’s safety, while Stuttgart’s already-faint European hopes took a hit after a third successive failure to win.
Flashscore Man of the Match: Andrej Ilic (Union Berlin)