The diagnosis came with an MRI on his left ankle on Wednesday morning.
Varejao tore his left Achilles in the Cavaliers' victory over the Minnesota Timberwolves on Tuesday night.
For Varejao, it is another in a series of leg injuries that have curtailed his career with the Cavaliers. For the team, it is a devastating loss of its best interior defender and a tested playoff performer. The Cavaliers will intensify what had already been a determined search for a center who can help protect the rim.
The loss of Varejao will move Tristan Thompson into the starting lineup for Cleveland.
Varejao signed a three-year, $30 million extension in November, which includes a partial guarantee on the final year of the contract.
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