Most everybody else found out Saturday, when the 18-year-old freshman quarterback led the Nittany Lions on to the field at MetLife Stadium.
Just a few months removed from playing high school baseball in Virginia, he confessed to a few nerves.
"After the first snap, it's football," he said.
The kid did OK.
Hackenberg threw for 278 yards and two touchdown passes and led Penn State to 23-17 victory against Syracuse. He went 22 for 31 and threw two interceptions as the second freshman to start a Penn State opener at quarterback since 1910.
"It's a big change," he said. "This coaching staff has helped me get through this. The team has helped me get through this, just really trying to immerse myself in the team and what the coaches are preaching every day."
The blue chip recruit hit Eugene Lewis with a deep pass down the middle and the receiver reached into the end zone for a 54-yard score that made it 23-10 with 11:39 left in the fourth quarter.
"I did the easy part. I just threw the ball up," Hackenberg said.
Penn State coach Bill O'Brien agreed, crediting Lewis for the route, fellow receiver Allen Robinson for drawing the defense and running back Zach Zwinak for picking up a blitz.
"On that play (Hackenberg) did the least amount of work," O'Brien said. "He made the throw and that's why he's on scholarship."
Hackenberg also hooked up with Robinson on a 51-yard touchdown in the third quarter.
Robinson, Penn State's leading receiver last season, unexpectedly did not play in the first half, but finished with seven catches for 133 yards. O'Brien declined to say why Robinson sat out the first half.
Oklahoma transfer Drew Allen got the start at quarterback for new Syracuse coach Scott Shafer, and finished 16 for 37 for 189 yards.
"I liked his moxie, I liked his energy and I liked his fight," Shafer said. "He made a couple of good throws, took some shots."
Hackenberg was far from perfect. His costliest mistake came in Penn State territory in the fourth quarter when he threw an interception to defensive lineman Robert Welsh, who returned the ball to the 1. On the next play, Jerome Smith plunged into the end zone to make it 23-17 with 6:58 left in the fourth.
Syracuse's last shot ended when Allen went deep down the sideline, but was picked off by Trevor Williams at the Penn State 25 with 1:53 left and no timeouts left for the Orange.
"It makes me sick to lose, but I had a blast," said Shafer, who was promoted from defensive coordinator after Doug Marrone left for the NFL.
Neither team revealed its starting quarterback until the offenses took the field, and in both cases the fans' choice prevailed.
O'Brien went with Hackenberg over junior college transfer Tyler Ferguson for all but one series. Shafer chose Allen over sophomore Terrell Hunt.
When Robinson finally got on the field, Hackenberg kept him busy. He caught the freshman's first two passes of the second half, including the long touchdown, when he got lost by the Syracuse secondary and weaved through tacklers after the catch to make it 13-3 Penn State.
Sam Ficken kicked three field goals, including a career-best 46-yarder early in the fourth quarter that made it 16-10.
Penn State's Stephen Obeng-Agyapong had an interception, a strip and fumble recovery, and a sack. The senior defensive back from the Bronx set up two field goals with his takeaways.
"Our defense bailed us out," O'Brien said. "They played a hell of a game."
Allen responded after Penn State's first touchdown with a perfectly thrown deep ball to Jeremiah Kobena that went for 55 yards. On the next play, Smith bounced outside and ran for a 10-yard score to make it 13-10 in the third.
"I went out there and I was comfortable," said Allen, the former backup at Oklahoma and top high school prospect. "I was calm. To be honest, I had a lot of fun."
The crowd of 61,202, a fairly even mix of Penn State and Syracuse fans for what was officially an Orange home game, finally had a reason to make some noise after a sleepy first half.
Preseason news for both teams was dominated by the same topic: Who would start at quarterback?
Hackenberg's arrival to Happy Valley was considered one of the biggest victories of O'Brien's short tenure at Penn State. He committed before Penn State was slammed by NCAA sanctions due to the Jerry Sandusky scandal. Nittany Lions fans worried Hackenberg might bail, but he stuck it out and the future is now for the freshman.
"It's been a big transition," he said. "But I got a lot of people ... my parents, coaches, to rely on."