Defender Roman Neustadter will be able to play in Euro 2016 after receiving his Russian passport.
Russia have named Roman Neustadter, who was born in Ukraine and does not have Russian citizenship, in their Euro 2016 squad.
Brazilian defender Naldo will join Schalke on a free transfer from Bundesliga rivals Wolfsburg this summer.
Stuttgart were relegated from the Bundesliga for the first time in 41 years after being beaten 3-1 by Wolfsburg on Saturday.
Schalke head coach Andre Breitenreiter will leave the Bundesliga club at the end of the season.
Bayern Munich were held 1-1 at home by Borussia Moenchengladbach on Saturday as Borussia Dortmund kept the Bundesliga title race alive.
Bayern Munich are 10 points clear after Robert Lewandowski scored twice in his side's 3-0 win over Schalke on Saturday.
Bayern Munich moved closer to a record fourth straight Bundesliga title as nearest challengers Borussia Dortmund were held 2-2 at Schalke.
Bayern Munich remain on course for a record-breaking fourth successive Bundesliga title with a 3-1 victory at Stuttgart.
Bayern Munich maintained their lead at the top of the Bundesliga with a hard-fought 1-0 win at home to Eintracht Frankfurt.
Schalke beat Borussia Monchengladbach 2-1 on Friday to move above the Foals into fourth place in the Bundesliga.
Bayern Munich remain five points clear of nearest Bundesliga rivals Borussia Dortmund after a goalless draw between Germany's top two sides on Saturday.
Mainz added some excitement to the Bundesliga season by becoming the first team to win at the Allianz Arena this season.
Borussia Dortmund kept up their pursuit of Bayern Munich at the top of the Bundesliga as they beat Hoffenheim on Sunday.
Gary Neville's Valencia smashed a Europa League record with the biggest aggregate win in the competition's history.
Borussia Dortmund kept up some pressure on Bayern Munich at the top of the Bundesliga with a 1-0 win at Bayer Leverkusen.
Bayern Munich came from behind to beat Darmstadt 3-1 and move 11 points clear at the top of the Bundesliga.
Schalke have announced that defender Joel Matip will join Liverpool on a free transfer at the end of the season.
Benedikt Howedes has signed a three-year contract extension to his contract with German club Schalke 04.
Jose Mourinho watched on as Borussia Dortmund failed to close the gap on Bayern with a goalless draw at Hertha Berlin.