Champion League contender Basel has sold two international midfielders to Bundesliga clubs two weeks before playing in the last-16 round.
Basel says Geoffroy Serey Die, who is with Ivory Coast preparing for the African Cup of Nations semifinals, has joined Stuttgart.
In another sale to Germany, Marcelo Diaz of Chile has joined Hamburger SV.
Basel did not reveal financial details of the transfers.
The Swiss champion says Serey Die's deal runs through June 2017 and Diaz has a contract through June 2016.
Basel hosts Porto in a last-16, first-leg match on Feb. 18. The return is in Portugal on March 10.
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