Barca confirmed Ter Stegen's Bosman signing yesterday, with the Germany goalkeeper agreeing a five-year deal.
"I have been 18 years with this club. I've known for some time that after this summer, for me and for Borussia we will be broken up.
"But it is a strange feeling, because I know I'm going to miss Borussia."
On moving to Barca he added: "Of course, I'm glad about my new job immensely."
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