Moore announced his decision in September to opt back in to play this season.
Purdue will be without star receiver Rondale Moore when it opens its season against Iowa on Saturday.
The school announced on Friday that Moore won't be available for the game, and officials did not provide additional information on his absence.
The Boilermakers will also be without head coach Jeff Brohm after he tested positive for COVID-19 on Sunday. Brohm is currently self-isolating at home for 10 days and Purdue petitioned the NCAA Football Rules Committee to allow him to call into the coaches' box to communicate with his staff during Saturday's game. However, The Athletic's Nicole Auerbach reports the school's request was denied.
Co-offensive coordinator Brian Brohm, Jeff Brohm's younger brother, will serve as acting head coach on Saturday.
On Thursday, Jeff Brohm told reporters that his team would have five or six players out against Iowa, but he did not name anyone specifically or provide an explanation.
The news of Moore's absence comes nearly one month after he decided to opt back in and play the 2020 season. On Aug. 6, he initially chose to sit out the season, citing the "unprecedented circumstances" surround the COVID-19 pandemic and saying he would prepare for the 2021 NFL draft.
After he opted back in, Moore told ESPN's College Football Live that felt safe playing this fall after the Big Ten enhanced its safety protocols, particularly its daily antigen testing.
"The Big Ten figured it out, Purdue was doing a great job of keeping us safe, and I felt safe coming back," Moore said. "For me, it was a no-brainer to come back to school and go prove what I think I'm worth.
"When I decided to leave, I couldn't get a lot of answers to the questions I was asking. Everyone was unsure. I'm a lot more comfortable than I was before I left."
Injuries limited Moore to just four games in 2019, but he turned in a sensational season as a freshman in 2018. He was a consensus first-team All-American and won the Paul Hornung Award as the nation's most versatile player. In 13 games, he caught 113 passes for 1,258 yards and 12 touchdowns. He also rushed for 212 yards with two scores and had 744 return yards on kickoffs and punts. Moore was the first true freshman consensus All-American in Big Ten history.