The German has agreed to a four-year contract.
Celtic have completed the signing of midfielder Mika Baur from Paderborn for a deal that could rise to £6.8million.
The German has agreed to a four-year contract.
It looked as though he may stay in his homeland after helping his team secure promotion last season but Celtic kept up the chase.
He scored four goals in thirty-six games in Bundesliga 2.

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