St. Peter's athletic department issued a statement Thursday, saying Holloway would sit out an exhibition Thursday night. He will also miss the Peacocks' first three games of the regular season.
The university said Holloway won't be available for comment because the matter remains under NCAA investigation. The school said the coach has been working with the NCAA enforcement staff in its investigation.
While St. Peter's didn't disclose the infraction, Holloway was on the staff of Seton Hall coach Kevin Willard before joining the Peacocks in April 2018.
Holloway was the Pirates' associate head coach at the end of his tenure at Seton Hall and among its chief recruiters.
Thompson transferred to Seton Hall in 2017. He sat out the 2017-18 season and played in 27 games for the Pirates last season.
Holloway, who posted a 10-22 record in his first season at the Peacocks' helm, can coach the team in practices. Assistant Ryan Whalen will handle the games.