An opening throw of 63.95m took world champion Stahl straight to the top of the leaderboard, before he was adjudged to have passed the automatic qualification mark of 66m with an improved second attempt of 67.66m, only for it to be chalked off for his heel clipping the front of the circle.
That seemed to upset his rhythm, as the disc brushed the netting on his third throw which also went down as a foul as he chose to step forward out of the circle. However, his opening attempt was enough to keep him in first place, clear of Lolassonn Djouhan of France (63.10m) and and Spain's Diego Casas (62.90m).
Three men in qualification group B threw further, topped by a 67.74m effort from Lithuania's Mykolas Alekna the world record holder, but Stahl was safely through and will be back for the final on 13th August, where he will attempt to add a first European gold to his three world and one Olympic titles.
Stahl's compatriot Jesper Ahlin competed in group B, but a best effort of 56.19m was only enough for 12th place in the group, thus he won't be joining the world champion in the final.
Larsson only other Swede through
In the men's 100m first round, Henrik Larsson recovered from a slow start to finish third in the opening heat in a time of 10.55 into a head wind. After the conclusion of the next two heats, it was confirmed that his time was quick enough - the 11th best in the field, with the top 12 progressing to the evening's semi-finals.
High-jumper and long-jumper Melwin Lycke Holm was taking part in the men's high jump qualification, where first-time clearances of 2.10m and 2.15m were followed by a first failure at 2.19m, but he recovered well to go clear at the second time of asking. However, three failures at 2.23m saw him exit the competition in 14th place, as he cut a frustrated figure after some near-misses.
Following a season's best of 56.11 in the first round on Monday, Moa Granat was back out on the track for the semi-finals of the women's 400m hurdles. On the inside lane, the 22-year-old put in another consistent run, clocking 56.13 to finish sixth, not enough to make it through to the final. Italy's Ayomide Folorunso came home first in a time of 53.93.
The Swedish vest will be on display in the evening session, as Larsson competes in his semi-final and Kajsa Roth participates in the women's pole vault qualification.