Wednesday pair Josh Onomah and Ash Baker will be looking to add to their international caps collection tomorrow evening.
Midfielder Onomah, on loan from Premier League Tottenham until the end of the season, and defender Baker are currently away on Under-21 duty with England and Wales respectively.
Onomah, who played over an hour of the Young Lions' goalless draw with the Netherlands on Thursday, will be hoping to feature in their European Championship qualifier away to Latvia.
Aidy Boothroyd's side sit top of Group D and require just five points from their remaining three matches to guarantee top spot and a place in next summer's tournament in Italy and San Marino.
The Young Lions will be without Leicester City duo Ben Chilwell and Demarai Gray, who have been promoted into the senior squad for the Switzerland friendly at the King Power Stadium.
As for Baker, the versatile Owls player is pushing to win his second Wales U21 cap when Rob Page's team take on Portugal in Bangor.
Baker, who has made three appearances this campaign, was utilised in a holding midfield role by his country in Friday's 2-1 European qualifying win over Liechtenstein. Striker George Thomas claimed a first half double as Wales held on to clinch a third win of the campaign in Group H.
Page has challenged his side to spring a surprise in their Euro qualifier.
"Portugal were outstanding when we played them away," admitted Page, whose side lost 2-0 in Chaves 12 months ago.
"We fell short having beat Switzerland a few days before but the players gave everything.
"We've had them watched and we know they've got quality, but why can't we go and get a result?
"If all aspects of the game come together on Tuesday, then we are confident going into it we can get the win."