The final in Madrid was pushed back a week due to changes in FIFA’s international calendar, which gave the victorious Reds little time to celebrate lifting No. 6.
Instead, they have left Merseyside—and the 750,000-strong crowd that welcomed them—for duty with their respective countries.
It is poised to be a busy summer, with the UEFA Nations League, Africa Cup of Nations and Copa America all set to be contested in June, before a return for pre-season with Liverpool.
Nineteen players from Klopp’s senior squad have received call-ups, with a handful of omissions.
The winner of that semi-final will play either Portugal or Switzerland in the final, with Xherdan Shaqiri set to represent the latter.
Other nations will play qualifiers for Euro 2020, with Dejan Lovren (Croatia), Simon Mignolet, Divock Origi (both Belgium), Andy Robertson (Scotland), Harry Wilson and Ben Woodburn (both Wales) all in action.
And with the CONCACAF Gold Cup being primarily held in the United States, Liam Millar will join the Canada squad as they take their place in Group A alongside Mexico, Cuba and Martinique.
Elsewhere, Caoimhin Kelleher is in the Republic of Ireland U21s squad for the Toulon Tournament, as is the recently departed Conor Masterson.
Kamil Grabara is likely to be No. 1 for Poland at the U21 Euros, with his main rival for the gloves, Bartlomiej Dragowski, pulling out due to injury.
Along with Fabinho, Lallana, Oxlade-Chamberlain and Sturridge, the likes of Alberto Moreno, Marko Grujic, Rafa Camacho, Rhian Brewster and Curtis Jones won’t be with their national teams, while Joel Matip and James Milner are both retired.
Anderson Arroyo is currently with Colombia at the U20 World Cup in Poland, and is expected to start in their quarter-final against Ukraine on June 7.
Vitezslav Jaros (Czech Republic U18s), Rhys Williams and Abdi Sharif (both England U18s) all played in the Slovakia Cup in May.
Liverpool’s Summer Internationals
Senior players called up: Alisson, Mignolet, Kelleher, Grabara, Van Dijk, Gomez, Lovren, Alexander-Arnold, Robertson, Henderson, Wijnaldum, Keita, Salah, Mane, Firmino, Origi, Shaqiri, Wilson, Woodburn
Notable youth: Arroyo, Millar
Not involved: Matip (retired), Moreno, Fabinho, Milner (retired), Lallana, Oxlade-Chamberlain, Grujic, Jones, Camacho, Sturridge, Brewster