Tigers sign Wallabies hooker
The 32-year-old has earned 78 Test caps and played in two World Cups, as well as making more than 140 appearances in Super Rugby with the Waratahs and Western Force.
"Taf is a fierce player with a huge amount of experience in Super Rugby and at Test level," said Tigers head coach Matt O'Connor.
"Now he is keen to experience rugby in the Northern Hemisphere and we're delighted that he has chosen to come to Tigers."
In 2005, at the age of 20, Polota-Nau achieved the rare feat of being capped by his country before he had played at Super Rugby level.
Polota-Nau said: "I'm really looking forward to experiencing what Northern Hemisphere rugby is about.
"To be privileged to do it with one of the most prestigious clubs of the English Premiership, Leicester Tigers – I believe that not only can I further my game individually but they have the capacity to add plenty more trophies to their illustrious cabinet and history."
Leicester are third in the Premiership table after seven games, trailing leaders Saracens by seven points.
Agence France-Presse
