The Brazilian will provide cover for first choice Pepe Reina, after passing a medical and agreeing terms on a deal at Melwood.
Samba style: Doni has agreed to join Anfield as Reina's understudy
Doni 31, made 179 appearances for the Italians and won the Coppa Italia twice and was also part of the side that clinched the Supercoppa Italiana.
Having already completed deals for Jordan Henderson and Charlie Adam, Doni is widely expected to be joined by Stewart Downing, after the Merseysiders had a ?20m offer for the winger accepted by Aston Villa.
Next stop, Anfield: Downing arrives at Melwood and is set to join Doni at Liverpool in a deal worth ?20million
Reds director of football Damien Comolli told the club's official website: 'We are delighted to sign Doni.'It's a position we felt we had to strengthen because it will allow our young goalkeepers to go on loan and get some experience at some point during the season, which is crucial in their development.'
The Reds are currently in Malaysia and face a select XI on Saturday as part of their pre-season tour of the Far East
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