Maribor - Maribor substitute Luka Zahovic pounced on an embarrassing defensive blunder from Sporting to rescue a 1-1 draw in stoppage time against the Portuguese club in their Champions League Group G opener on Wednesday.
The 18-year-old Slovenian forward headed home a loose ball in the second minute of injury time after Sporting's centre-back pairing fluffed clearances in a panicked attempt to hold on to a lead given them by Nani's devastating strike.
The Manchester United outcast had cut in from the right in the 80th minute and drilled a left-foot shot into the bottom corner in the game's one moment of outstanding quality.
It looked enough to give Sporting the points before the Slovenian champions hit back on their return to the Champions League group stages after 15 years away.
Sporting dominated possession and territory but were wasteful going forward - epitomised by Nani's mixed overall performance - and Maribor will feel as though they deserved something out of the game.
Had their finishing been more clinical, especially that of Brazilian striker and captain Tavares, the home side could have emerged with even more at the Ljudski stadium.
Tavares was a powerful presence throughout for Maribor, though Nani was also denied by a sharp save from Jasmin Handanovic who kept out his half-volley.
Both sides had hit the woodwork in the first period. First Sporting's Andre Carillo clipped the crossbar with a right-foot curler before Maribor defender Aleksander Rajcevic thundered a header on to the base of Rui Patricio's post from a brilliant free kick by Dare Vrsic.