Middlesbrough winger Viktor Fischer has joined Bundesliga side Mainz for an undisclosed fee.
The 23-year-old joined Middlesbrough for around £3.8m from Ajax last summer and made 16 appearances for the club.
The Denmark international struggled with a knee injury for much of the season and failed to score for the Teessiders, but made three assists.
He joins Mainz, who finished 15th in Germany's top tier last season, on a four-year deal.
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