Papastathopoulos, 30, had spells with AC Milan, Genoa and Werder Bremen before joining Dortmund in 2013, and he has racked up almost 200 appearances for the Bundesliga giants.
He helped the club to win the DFB-Pokal in the 2016-17 season, also claiming a brace of DFL-Supercup crowns during his time at Dortmund.
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Anthony Kennedy, the Supreme Court justice who retires at the end of this month , has more than earned his government pension. Circuit Court of Appeals Judge Brett Kavanaugh and Seventh Circuit Court of Appeals Judge Amy Coney Barrett, both women.
The Greece global becomes the latest player to join the new era under manager Unai Emery.
Sokratis Papastathopoulos has completed his move to Arsenal from Borussia Dortmund.
He follows Pierre-Emerick Aubameyang and Henrikh Mkhitaryan, who joined from Manchester United last season after impressing during his time in the Bundesliga.
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Marcelo is medicated and with medication the tendency is that the response is good and that he can play. "He is a player we will have to watch out for and he's really important to Brazil's game".
There had been rumours for weeks about the Greek defender making the switch from Borussia Dortmund and now everything is official.
"I feel very good, it is my first day here, everything is special, it is a lovely moment".
"I spoke [to them] a lot times", he said.
'Arsenal is one of the three biggest teams in the Premier League and one very big club. I like that my team doesn't take goals.
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Putin did not attend the match in Moscow and it is not known if he will attend Russia's quarter-final. Russian Federation will meet Croatia or Denmark in the last eight in Sochi on Saturday.