Later, O'Brien said of McGloin: "He's just the one that tells me every week that we need the quarterback draw."
Turning serious, he concluded: "He's a great kid, a fun kid to coach. I love coaching competitive people, and he's a very competitive guy."
McGloin got the job done after the Nittany Lions had fallen behind by 28-17 in the final minute of the third quarter. He accounted for two of his team's three touchdowns in the fourth, hitting Allen Robinson with a 6-yard touchdown pass and later running it in with 2 minutes, 37 seconds to play.
"He understands it's a 60-minute game," O'Brien said. "He's grown up a lot. When you're a senior and playing your last few games here at Penn State, that means a lot to him. Again, I can't say enough about Matt McGloin. He's gotten the job done to this point in the year."
For the game, McGloin threw two touchdown passes to raise his season total to 12, tied for first in the Big Ten, and added his fifth rushing TD of 2012. He has accounted for 17 of the Lions' 21 offensive touchdowns.
McGloin set a Penn State record Saturday with 35 completions, and his 51 attempts tied him for second all-time. His 282 passing yards marked the 12th time he had thrown for more than 200 yards in a game, fourth on the career list behind Kerry Collins, Zack Mills, and Daryll Clark.
"We had a full quarter to play," McGloin said of the comeback. "We've scored more than 11 points in a quarter before and we knew we were capable of doing it. We had been able to move the ball on them all day - we had just stopped ourselves a few times. We knew we had to make something happen."
The dramatic victory enabled the Lions to enter their bye-week on a positive note. O'Brien said he would stay close to a business-as-usual week, which means forgetting about the win by the time the players report Monday for a review of the game film.
"A win like this is going to make the bye week a pleasurable bye week," center Matt Stankiewitch said. "You really don't want to go into a bye week with a loss. That would have been horrible. We're not going to settle for anything less than winning."
The 301-pound Stankiewitch later couldn't help but poke a little fun at the TD run by McGloin, one of his roommates.
"If I was running the ball, I probably would have gotten in there a little faster than him," he said, "but it wouldn't have been that dramatic. That's what happens when you have an instinctive quarterback that makes plays."
Campbell's productive day. Northwestern sophomore safety Ibraheim Campbell, a Chestnut Hill Academy graduate, had a terrific day with 14 tackles and two pass breakups but called the loss "extremely disappointing."
"We will be mortified after this loss," Campbell said. "It's easy to get excited after wins, but after taking a loss in a game that you expected to win, our true character will show as a team, and I'm looking forward to it."
Contact Joe Juliano at email@example.com, or follow on Twitter @joejulesinq.