Thomas Tuchel's highly touted side wavered in their Bundesliga ambitions either side of the international break, with a defeat to Bayer Leverkusen and a draw against Hertha Berlin leaving them languishing in fifth domestically.
But in the first half at the Estadio Jose Alvalade they relocated the rousing European form that resulted in a thrashing for Legia Warsaw and pegged back Real Madrid earlier in the round-robin phase.
Pierre Emerick-Aubameyang's third goal of the competition settled early nerves and set in motion a dazzling display from Dortmund's star striker.
Julian Weigl's sumptuous first goal for the club doubled Dortmund's advantage but Jorge Jesus' hosts redoubled their efforts after the interval and substitute Bruno Cesar's indirect free-kick set up a thrilling finale, where few could have begrudged them a share of the spoils.
Sporting began in enterprising fashion but Aubameyang gave Tuchel's side a ninth-minute lead with a formidable demonstration of his talents.
The pacey forward outstripped Ruben Semedo to latch onto Mario Gotze's ball down the right flank before cutely lobbing Rui Patricio.
Aubameyang almost had cause to repeat his summersault celebration when Rui Patricio clawed his header from Gotze's searching cross out of the bottom left corner.
Bas Dost nodded wide for Sporting in the 29th minute, while Dortmund goalkeeper Roman Burki reacted well to prevent Elias capitalising on Felix Passlack's indecision.
Aubameyang glanced past the post from Ousmane Dembele's centre, while Patricio atoned for his own fumble by denying the goalscorer his second.
At the other end, Burki was fortunate referee Damir Skomina ruled Dost blocked his failed attempt to claim a corner, meaning Sebastian Coates clattered meaninglessly into an unguarded net.
Aubameyang then escaped three defenders to thump an effort off target, but Dortmund had a second as the half ticked down from an unfamiliar source.
Weigl stylishly beat William Carvalho and Elias before a moment of hesitation from Semedo allowed the midfielder to rifle into the bottom left-hand corner from 25 yards.
Sporting continued to press after the interval, with Dost providing a thorough workout for the Dortmund centre-back – one of whom erred significantly in the 65th minute.
Marc Bartra's backpass at close quarters meant Burki was forced to handle and, following the obligatory lengthy deliberation, Carvalho touched the ball with the sole of his boot and Bruno Cesar smashed through the massed ranks of yellow on the goalline.
Dost's latest header flew wide moments after Tuchel reshuffled his now creaking defence by replacing Bartra with Lukasz Piszczek.
An injury to right-back Matthias Ginter meant the enforced introduction of Sebastian Rode and Burki scrambled to prevent a Dost tap-in with 13 minutes remaining.
Christian Pulisic planted a dipping strike against the Sporting crossbar and it was breathing space Dortmund appeared to need when substitute Andre agonisingly failed to turn in Gelson Martins' strike across goal.
Tuchel's men would ultimately battle through a lengthy period of stoppage time following an injury to full-back Passlack, meaning Sokratis Papastathopoulos was the only member of their starting back four left standing at the final whistle.
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