Per an official announcement from the team, Oladipo's MRI revealed he suffered a ruptured quad tendon in his right knee.
Oladipo suffered the injury late in the second quarter of Indiana's 110-106 win over the Toronto Raptors on Wednesday.
"It is threatening to his explosiveness and athleticism," Wojnarowski wrote. "It's a challenging road back."
Parker's injury occurred while he played for the San Antonio Spurs against the Houston Rockets during Game 2 of the Western Conference Semifinals in May 2017. He missed the first 19 games of the 2017-18 season before returning on Nov. 27.
The loss of Oladipo is a huge blow for the Pacers, who are the No. 3 seed in the Eastern Conference. He leads the team with 18.8 points per game and ranks second with 5.2 assists per game.
Tyreke Evans will likely get first crack at filling Oladipo's shoes. The 29-year-old has been a disappointment after signing with the Pacers last summer. He's averaging 10.9 points per game and shooting 35.6 percent from three-point range.
Indiana (32-15) trails the Raptors and Milwaukee Bucks by 2.5 games for the top spot in the Eastern Conference playoff race.