The much-coveted RB Leipzig striker was unable to complete the full 90 in the recent 1-1 draw with Serbia, where a late Luka Jovic header cruelly denied Slovenia their maiden win at a Euros Finals.
However, Sesko has been training as normal over the weekend and should take his rightful place in Kek's 4-4-2, but a trio of untimely new concerns have emerged for the Slovenia boss, who could not call upon Jan Oblak for training on Saturday.
Midfielder Adam Gnezda Cerin was nowhere to be seen either, while Timi Max Elsnik - who also started in the centre against Serbia - had to leave early, although there is no suggestion that they are nursing serious issues.
Jon Gorenc Stankovic is waiting in the wings should he be required, but Cerin and Elsnik should be given the green light to pair up in the middle, in between Jan Mlakar and Petar Stojanovic.
Veteran attacker Josip Ilicic is still waiting for his first minutes at the European Championships and will certainly not receive them from the first whistle in Cologne, where Andraz Sporar and Sesko will likely resume their partnership.
One alteration at the back could see David Brekalo come back in for Vanja Drkusic, but Erik Janza, Jaka Bijol and matchday two goalscorer Zan Karnicnik ought to continue in front of Oblak, assuming that the Atletico Madrid man is not carrying a severe problem.
Slovenia possible starting lineup:
Oblak; Karnicnik, Brekalo, Bijol, Janza; Mlakar, Elsnik, Cerin, Stojanovic; Sporar, Sesko