Albion have snapped up Switzerland under-21 midfielder Nzuzi Toko on a free transfer.
The 23-year-old will officially sign for three years on July 1 when his deal with Swiss runners-up Grasshoppers expires.
He completed a medical at the Amex today.
Seagulls chairman Tony Bloom revealed the deal had been put in place before the season ended.
He said: "We concluded a deal to sign Toko before their season and ours had ended.
"Now that Toko has completed the season at Grasshoppers Zurich we are delighted to welcome him to Brighton and Hove Albion."
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