The team announced Ward's diagnosis Monday and said the former All-Star goalie will not require surgery.
The team says Ward suffered a third-degree sprain to his medial collateral ligament midway through the second period of Sunday night's 3-2 win at Florida.
The team-issued timeline places Ward's potential return in mid- to late-April. The regular season ends April 27.
The injury makes backup Dan Ellis the team's No. 1 goalie. Ellis is 3-2-1 with a 2.53 goals-against average in his first season in Carolina.
The team then called up Justin Peters from Charlotte of the AHL to serve as Ellis' backup. Peters is 11-11-3 with a 3.23 GAA in 28 career NHL games during the previous three seasons.