Holtmann said he'll do his best to focus on the game and the players, but he admitted he'll have to keep his emotions in check during the fifth-place game of the tournament's Motion Bracket.
"You know, it's not ideal. It's not ideal," Holtmann said after his team's win over Stanford on Friday. "Our coaching staff has a lot of affection for those players and certainly for that community. It's certainly not ideal, not how we would have drawn it up. It's really about the players. As much as possible, I want it to be about their players and our players competing."
Ohio State abruptly dismissed Thad Matta in June, citing subpar performances and poor recruiting. The school then turned to Holtmann, who had led Butler to the Sweet 16 in March, in one of the latest major coaching switches of the offseason.
Kyle Young, a top-100 recruit who had signed with Butler, followed Holtmann to Ohio State, too.
Butler replaced Holtmann with LaVall Jordan, a former player who led UW-Milwaukee to the Horizon League tournament championship game as a 10-seed last season.
When he was asked about Sunday's matchup, Holtmann paused for six seconds and looked down at his stat sheet before he responded. It appeared he was trying to collect himself before he spoke.
"As much as possible, in those two hours, you try to eliminate the emotion of it," Holtmann said. "They're competing to win every possession, and so are we."
Ohio State's Keita Bates-Diop grinned when he was asked about Sunday's game and any additional motivation players might have.
"Why?" he said. "What's so big about the matchup?"
Holtmann added later: "I really don't think that our players are going to do anything differently because I coached at Butler last year. They're going to be who they are, and I want them to be who they are."