Celtic will complete the signing of midfielder Massimo Donati from AC Milan on Friday, after undergoing a medical.

The 26-year-old has already agreed a four-year contract ahead of a deal that will reportedly cost Celtic £3m.

He will be the Glasgow club's fourth signing of the summer and the deal will take their spending to more than £8m.

A Celtic spokesperson said: "We are delighted that Massimo has signed. He is a player of real quality who we're sure will be a great addition."

Donati cost the Italian giants £10m when he signed from Atalanta in 2001.

He spent last season back on loan to Atalanta, having previously been farmed out to Parma, Torino and Sampdoria.

His previous club had been one of those reportedly interested in securing his signature, along with Sampdoria and Palermo.

But he decided on the Scottish champions after arriving in Glasgow earlier this week for negotiations.

Celtic have also been linked with a move for Sampdoria midfielder Gennaro Delvecchio.

But Donati will be the first to complete a deal, becoming Celtic manager Gordon Strachan's fourth summer capture.

Scott Brown joined from Hibernian for £4.4m, while Easter Road team-mate Chris Killen was snapped up on a Bosman and fellow striker Scott McDonald arrived from Motherwell for £700,000.