The Lakers announced their latest major injury Monday.
Kelly played only five minutes in the Lakers' blowout loss to Golden State on Sunday night. An ultrasound exam revealed the tear.
Kelly had played in only three games this season due to previous injuries to both hamstrings. The second-year pro from Duke excelled as a rookie last season.
While Kelly is sidelined, the Lakers expect Nick Young to make his season debut Tuesday at Atlanta. He had thumb surgery last month.