The 20-year-old Nigeria international scored a sublime solo goal, after Ederson had opened the scoring in Germany, to earn Vladimir Petkovic's men a fine away win
Ederson put the Italians ahead against the run of play midway through the first half of an open and engaging last-16, first-leg clash at the Mercedes-Benz Arena, and Ogenyi Onazi sealed a fine away win for Vladimir Petkovic's men with a stunning solo effort 11 minutes into the second half.
The final scoreline was perhaps a tad harsh on Stuttgart, which wasted a number of fine openings. Indeed, after having had the better of the early exchanges, the Germans went desperately close to opening the scoring 16 minutes in when the lively Christian Gentner stood the ball up wonderfully well for Shinji Okazaki, who made a tremendously clean connection with the cross, only to be denied by a fine reaction save from Federico Marchetti.
The Lazio goalkeeper was called into action again less than 60 seconds later, this time keeping out a header from Serdar Tasci, as the hosts began to up the ante. It felt like a goal was coming. The only surprise was that it came at the other end, but then, Stuttgart only had itself to blame in that regard.
Both William Kvist and Arthur Boka made a mess of trying to clear a routine cross into the area and their ineptitude was ruthlessly exploited by Ederson, who swivelled on the ball before firing it left-footed past Sven Ulreich and into the bottom right corner of the goal.
Stuttgart should have been level just before the break but Okazaki somehow construed to head wide from less than five yards out, after being the recipient of the most perfectly placed cross from Gentner.
Shocking as that miss was, it did at least lift the home side, which began the second period brightly. However, it had merely been lulled into a false sense of security once more, with Lazio all but putting the game, and perhaps even the tie, beyond it with a second away goal shortly before the hour mark.
In fairness to Stuttgart, it appeared to be in very little danger of conceding when Onazi picked up possession in midfield. However, the 20-year-old Nigerian jinked his way past two would-be tacklers before coolly lifting the ball past Ulreich and into the back of the net.
Once again, though, the hosts had an almost immediate chance to get back into the tie. Once again, though, Okazaki squandered it. In fairness to the Japanese, it was an opening all of his own making, the 26-year-old attacker lifting the ball over Lorik Cana before dragging his subsequent volley just wide of the far post.
Still, it was an opportunity that Stuttgart could ill-afford to miss because it was ultimately unable to find a way through its opponent's supremely well-marshaled defense. The Germans now face the rather unenviable task of having to score at least twice in Rome next week if they are to have any hope of reaching the quarterfinals.