Source: The Mavericks believe J.J. Barea tore his right Achilles tendon. Barea, 34, a longtime Dallas fan favorite who played a key role on the 2011 title team, is averaging 10.9 points and 5.6 assists as the Mavs' sixth man this season.
— Tim MacMahon (@espn_macmahon) January 12, 2019