The striker played around 20 minutes in a 2-0 defeat to Kosovo, marking his first minutes since the end of last season. Though unable to change the outcome, Isak looked reasonably sharp and may be fit enough for another cameo appearance for the Reds in a few days' time.
"This was the maximum number of minutes I could give him," Sweden boss Jon Dahl Tomasson told Viaplay post-match.
"We have talked in recent days about what risks there are and what is not a risk. It is extremely difficult to take a risk.
"I want to play him every minute. You can see right away that he is dangerous and creates things. But we also need him next month, the month after that, and next year."
For Liverpool, the international break has offered little respite, with several key players still representing their countries.
Mohamed Salah is expected to line up for Egypt later today, while French duo Ibrahima Konate and Hugo Ekitike are also set to feature in World Cup qualifying.
Hungary's Dominik Szoboszlai and Milos Kerkez remain involved as well, ensuring a demanding week for many of Arne Slot's squad.
England are preparing to face Serbia, though Curtis Jones was a notable omission from Thomas Tuchel's latest squad, leaving him sidelined from international duty.
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