Celtic have signed Sweden centre-half Carl Starfelt from Rubin Kazan on a four-year contract.
The 26-year-old, who has three caps, moves to the Scottish Premiership club for a reported fee of £4m subject to international clearance.
Starfelt played 31 times, all starts, for Kazan last season as they finished fourth in the Russian Premier League.
His signing comes on the same day Celtic sold Norway centre-back Kristoffer Ajer to Brentford.
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"Carl is an experienced player and someone with the attributes to be a real success at Celtic," said manager Ange Postecoglou.
"He is a strong, athletic and committed defender and will add quality to our squad."
Celtic added that the player will join the squad "as soon as possible" after serving a period of quarantine.
The Swede started his career with Brommapojkarna in his homeland and joined Kazan from IFK Gothenburg in 2019.
He signed a three-year contract extension in February this year, but departs the Russian club after 42 appearances and three goals in his two-year spell.
Starfelt, who missed out on a place in Sweden's squad for Euro 2020, becomes Celtic's fourth senior summer signing under new manager Postecoglou following the arrival of defender Osaze Urhoghide and midfielder Liam Shaw, both from Sheffield Wednesday, and winger Liel Abada from Maccabi Petah Tikva.
Find all the latest football transfers on our dedicated page.