O'Brien, wrapping up his seventh year on the job at Ohio State, discussed the issue with reporters for more than five minutes inside the team's locker room.
The coach was asked if he is committed to coming back to OSU for an eighth year.
"Why would you ask me that?" O'Brien said.
"Right now, I have every reason to want to be back," he added.
The coach was then asked what he would do if he or one of his close associates were contacted by SJU.
"Let me see if I can make this as clear as I can: I am not interested in talking about other situations," he said. "What I am interested in telling you is I am not a candidate for St. John's. I am not a candidate for the St. John's job.
"I have said repeatedly that Ohio State has been great to me. Andy Geiger is the best. I like Ohio State. I've said this repeatedly -- this is where I hope to be coaching."
O'Brien was then asked what would happen if St. John's made him a candidate.
"How are they going to make me a candidate?" he said. "Some list on the Internet?
"I have no interest in continuing this discussion," he added, eliciting some laughter.
"But let's be clear on this -- I am not a candidate."
Several reporters joked that it could happen the same way he became a candidate at Ohio State seven years ago.
"Thanks a lot for that," O'Brien said, again eliciting laughter.
Reporters took one more crack, trying to get O'Brien -- a New York City native -- to bite on the chance St. John's will call.
"That is not going to happen," O'Brien said. "I doubt it."
The Buckeyes ended the year 14-16 after their loss to the Hoosiers. That leaves O'Brien's record at OSU at 133-88 and his 22-year head coaching mark at 368-305.
O'Brien would have four starters and nine letterwinners back next year. Plus, he and his staff will be adding three recruits in guard Jamar Butler and forwards Jermyl Jackson-Wilson and Matt Terwilliger.
But, clearly, O'Brien admits that some things have to change if this program will return to the top of the Big Ten.
"We talk about how we need to commit to having a tougher approach and being tougher defensively," O‘Brien said. "We need to be more disciplined in everything we do, offense and defense."
O'Brien said his team's easygoing nature may have been part of its downfall this past season.
"We have a really nice group of guys," he said. "Everybody got along with everybody else. I don't know if there was any one personality that could step up and challenge people, maybe at the risk of stepping on some toes. We didn't have that this year."