Celtic have signed Croatia international full-back Josip Juranovic from Polish champions Legia Warsaw for an undisclosed fee.
The 26-year-old will sign a five-year deal once the transfer has received international clearance.
Juranovic becomes manager Ange Postecoglou's eighth signing of the summer transfer window.
"We have so many challenges ahead of us and Josip will add important quality and depth," the Celtic boss said.
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"As I have said before, everyone at the club has been working hard to add to our squad and we have made good progress. I am really pleased to bring Josip in to support the rest of the boys."
Celtic are reported to have paid £2.5m for Juranovic, who began his career at Hajduk Split in his homeland before moving to Legia Warsaw last summer.
He made 41 appearances for the Polish side across last season and the beginning of this campaign, registering 10 assists and two goals - the latest coming in Thursday's 2-2 draw away to Slavia Prague in Europa League qualifying.
Juranovic, who has 10 caps for Croatia and featured at the Euros this summer, will provide competition at right-back for Anthony Ralston, who has been first choice for Celtic so far this season.
Celtic have also been linked with a move for Hibernian striker Kevin Nisbet.
"I'm not quashing, denying or confirming," Postecoglou told BBC Scotland before Celtic's win against St Mirren on Saturday.
"There's work we are doing off the field and hopefully we can make some announcements in the next few days."
Find all the latest football transfers on our dedicated page.
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