"It all starts with that leadership. I believe these guys have put that game behind them. We all have, and it's time to move on. We started that process" Monday.
In moving on, O'Brien knows that he has to address the mistakes that were made by the Nittany Lions (5-3, 3-1 Big Ten) during Saturday's 35-23 loss. And there were quite a few given an anemic rushing attack, a pick-six thrown by Matt McGloin and a defense that allowed a 50 percent success rate on third-down conversions by the Buckeyes.
"I don't think anyone played the way that they were capable of playing on either side of the ball or on special teams," he said. "Again, give Ohio State credit. . . . I don't think anyone played particularly well, nor did we coach well that night."
O'Brien said there were missed opportunities on offense, defense and special teams. He said the offensive line was not solely responsible for the four sacks of McGloin, that the quarterback may have held the ball too long, or that a back or tight end missed a blitz pickup.
Penn State's erratic special teams had their ups - a blocked punt that led to the Nittany Lions' first touchdown, punts from Alex Butterworth that pinned Ohio State inside its own 16 four times - and their downs.
"I thought our kickoff return team was terrible," O'Brien said. "We've got to do a better job there. We've got to coach it better. We've got to get going there and do a better job."
Bill Belton, the starting tailback, caught all six kickoffs by the Buckeyes but averaged fewer than 14 yards per return. Penn State started just one of those drives outside its own 25.
Asked if Belton will return to that spot against Purdue, O'Brien replied: "We'll compete in practice, and we'll decide that probably Friday night."
O'Brien said tight end Kyle Carter, the Lions' No. 2 receiver with 35 receptions, is day-to-day with an ankle injury suffered as he caught a touchdown pass in the fourth quarter against Ohio State. The coach added that Carter "seems to be doing OK."
Purdue (3-5, 0-4) is reeling. After starting the season 3-1, with their only loss coming on a last-second field goal to undefeated Notre Dame, the Boilermakers have lost four straight, including last week's 44-28 loss to Minnesota in which the Golden Gophers scored all their points over a span of 25 minutes, 46 seconds.
The latest defeat prompted a statement Monday by athletic director Morgan Burke expressing disappointment over the performance of the football team, which had "high expectations" for this season.
"I didn't pay a whole lot of attention to it or didn't try to read between the lines," Purdue coach Danny Hope said Tuesday. "I think it's a pretty generic statement and very similar to the one that was posted about this time last year. Our focus is to prepare our football team for a game this Saturday."
O'Brien said Purdue has a talented defense and an offense that presents "a lot of challenges." The Boilermakers will switch quarterbacks this week, going with sixth-year senior Robert Marve in place of regular starter Caleb TerBush.
Contact Joe Juliano at firstname.lastname@example.org or follow on Twitter @joejulesinq