Saints defender Yoshida and his Japan teammates have been placed in Group A, and will take place in the tournament-opening game against hosts Brazil tomorrow evening.
Ramírez, meanwhile, is in the Uruguay squad that has been drawn into Group B of the eight-team competition, with their first game seeing them take on current World Cup holders Spain on Sunday.
The group stage will last until Sunday 23rd June, at which point the top two sides in each group will progress to the semi-finals.
If Japan and Uruguay both make it out of their respective groups, the Southampton duo could well come head-to-head in the semi-finals or indeed meet in the final or third-place play-off.
The schedule of group-stage games featuring Yoshida and Ramírez is as follows:
Saturday 15th June, 8pm BST kick off
Brazil vs Japan – Estádio Nacional, Brasília
Sunday 16th June, 11pm BST kick off
Spain vs Uruguay – Arena Pernambuco, Recife
Wednesday 19th June, 11pm BST kick off
Italy vs Japan – Arena Pernambuco, Recife
Thursday 20th June, 11pm BST kick off
Nigeria vs Uruguay – Arena Fonte Nova, Salvador
Saturday 22nd June, 8pm BST kick off
Japan vs Mexico, Estádio Mineirão, Belo Horizonte
Sunday 23rd June, 8pm BST kick off
Uruguay vs Tahiti – Arena Pernambuco, Recife
The winner of Group A will then take on the runner-up from Group B in Belo Horizonte on Wednesday 26th June, with the top team from Group B facing second from Group A in Fortaleza the following day.
The Confederations Cup final in Rio de Janeiro and third-place play-off in Salvador both take place on Sunday 30th June as the tournament comes to a close.
Now in its 22nd year, the Confederations Cup brings together the winners of FIFA's six regional confederation championships plus the current World Cup holder and the host of the next World Cup.
The tournament takes place every four years, and since 2005 has been held in the nation next due to host the World Cup.
The participants in the 2013 Confederations Cup are:
- Brazil (2014 FIFA World Cup hosts)
- Spain (2010 World Cup winners)
- Japan (2011 AFC Asian Cup winners)
- Mexico (2011 CONCACAF Gold Cup winners)
- Uruguay (2011 Copa América winners)
- Tahiti (2012 OFC Nations Cup winners)
- Italy (UEFA Euro 2012 runners-up)
- Nigeria (2013 Africa Cup of Nations winners)
Italy take their place at the Confederations Cup due to Euro 2012 winners Spain having already qualified by virtue of their World Cup victory two years earlier.
Uruguay are currently rated as fourth-favourites by the bookmakers, while only outsiders Tahiti have longer odds than Japan. Hosts Brazil are narrow favourites ahead of Spain.
The tournament will round off busy summers for Ramírez and Yoshida, who immediately joined up with their national teams when the 2012/13 Premier League season came to an end.
The pair have both played friendlies and 2014 FIFA World Cup qualifiers ahead of the Confederations Cup with Japan and Uruguay both notching up confidence-boosting results before their journey to Brazil.
After a disappointing friendly defeat to Bulgaria, the Samurai Blue recovered to record a draw with Australia that saw them become the first non-hosting side to qualify for next summer's World Cup finals.
Yoshida was then rested as Japan rounded off their qualifying campaign with a 1-0 win over Iraq in Qatar earlier this week, meaning they will go into their Group A games with Brazil, Mexico and Italy with confidence.
Uruguay, meanwhile, upset the odds somewhat when they defeated France 1-0 in Montevideo, with Ramírez having a hand in Luis Suarez's winner.
La Celeste then boosted their hopes of qualifying for the World Cup when they won 1-0 in Venezuela on Tuesday evening, with the Saints playmaker impressing before being substituted with an hour gone.