Celtic defender Virgil van Dijk is expected to join Southampton on Tuesday for a fee in the region of £11.5m, according to Sky sources.
The 24-year-old is also understood to have successfully passed his medical on Monday night ahead of a move to St Mary's.
Van Dijk joined Celtic from Groningen in 2013 and has since helped the Hoops win two Scottish Premier League titles, making 111 appearances for the club.
He was named in the Netherlands' provisional squad for this week's Euro 2016 qualifiers with Iceland and Turkey, but was then omitted from the final pool, leaving him free to secure a move to the Premier League.
He will become Southampton manager Ronald Koeman's ninth signing of the summer transfer window and will join Dutch compatriots Jordy Clasie and Maarten Stekelenburg at the club.
Celtic have already moved to fill the void left by Van Dijk, agreeing a fee with Dinamo Zagreb for Croatia Under-21 defender Jozo Simunovic.
Manchester United defender Tyler Blackett also joined the Scottish champions last week on a season-long loan deal.
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