Emil Krafth and new signing Jeff Hendrick have been called up by their respective national teams for UEFA Nations League fixtures next month.
Krafth has been named in the Sweden squad for games against France (Saturday, 5th September) and Portugal (Tuesday, 8th September), both in Solna.
The Ljunby-born defender has won 21 caps for his country and played for them at the 2018 World Cup in Russia.
Hendrick, meanwhile, has been named in Stephen Kenny's first Republic of Ireland squad for fixtures against Bulgaria (in Sofia on Thursday, 3rd September) and Finland (in Dublin on Sunday, 6th September).
The midfielder will be looking to add to his 54 caps and two goals.
Both players will therefore miss Newcastle United's final pre-season friendly of the summer, against Stoke City on Saturday, 5th September.
Martin Dúbravka missed out on Slovakia's squad for games against Czech Republic and Israel due to a heel injury which is expected to sideline him for several weeks, while Fabian Schär is recovering from the dislocated shoulder which ruled him out of the final games of last season so has not been named in Switzerland's squad for matches against Ukraine and Germany.