One of the title challengers for many months in the 2025 Allsvenskan, AIK fell away in the final weeks of the season to eventually finish seventh, and Gnaget don't seem to have reversed their form just yet under new boss Jose Riveiro, as they lost 2-0 at home to Vasteras.
The second-tier champions struck twice in the first half, through Taonsa Axel and Jonathan Ring, to give them a real confidence boost ahead of just their second top-flight campaign this century.
That puts Gronvitt top of what is shaping up to be a fascinating Group 7, ahead of Svenska Cupen holders Hacken, who held on for a narrow 2-1 victory at home to Superettan side Oddevold.
Adrian Svanback and Silas Andersen - who scored the winning penalty in the 2025 final - struck either side of the break for the cup specialists, but a late Leonardo Shahin penalty made for a nervy finish in Gothenburg.
Record-breaking Allsvenskan champions Mjallby showed no sign of their form dropping off in 2026, as they won their first competitive game with Karl-Marius Aksum as head coach, beating Kalmar 2-0 at home to top Group 1, courtesy of strikes from Elliot Stroud and Jacob Bergstrom.
The were one of the many top sides who avoided an upset in the first round of group matches, as Malmo did enough to beat Varberg 1-0 and Hammarby struck twice after half-time to get the better of Brage, 2-0.
In Group 8, the gap between the Allsvenskan and the rest was clearly evident, as Sirius won 6-0 at home to Sundsvall and Elfsborg benefitted from an early red card to beat Helsingborg 4-0.
On Monday evening, the opening round was completed in Gothenburg, where GAIS were out of sight by half-time, winning 3-0 against Landskrona.
Review all the Svenska Cupen results and standings on Flashscore.