UNIVERSITY PARK — Penn State’s first game under Bill O’Brien featured a promising start — and a cruel ending.

With a charged crowd of 97,186 fans that included more than 200 former players and 600 of their fellow student-athletes, the Nittany Lions opened the O’Brien era with a 24-14 loss to Ohio University on Saturday at Beaver Stadium.

It’s safe to say Penn State, which lost its first opener since falling to Miami 33-7 in 2001, let this one trickle away.

Holding a 14-3 lead and forcing Ohio into a third-and-7 early in the third quarter, a potential interception caromed off safety Stephen Obeng-Agyapong. The ball dropped into opportunistic wide receiver Landon Smith’s hands.

Smith raced into the end zone for a 43-yard touchdown, the first of three the Bobcats registered in a second half where they outscored Penn State 21-0.

The second half looked nothing like the first half.

The Bobcats, who joined Toledo as the second Mid-American Conference team to defeat Penn State, outgained the Nittany Lions 301-115 in the second half. Penn State’s defensive front, which was viewed as a preseason strength, ended the game with just one sack and one tackle for a loss.

“We just have to make plays,” sophomore cornerback Adrian Amos said. “We had the opportunity to make plays. There were two interceptions we dropped. It just wasn’t our day. We felt if we play our game, it’s a whole different story. We have to play better.”

Penn State’s players handled the loss better than their coach. O’Brien, who replaced Joe Paterno in January, struggled explaining his head coaching debut after the game.

He answered multiple questions in his postgame news conference by simply replying, “No.” His other answers provided little insight.

“Nothing surprised me,” he said. “Like I said, we have to do better. We have to coach better. We have to better with these kids than we did.”

O’Brien was the first coach to lead Penn State into a new season since 1966. Paterno, O’Brien’s predecessor, was fired last November and died of lung cancer in January.

From a tactical standpoint, the start of the O’Brien era contrasted the end of Paterno’s 46-year reign.

Quarterback Matt McGloin established a rhythm early, completing his first five passes and leading the Nittany Lions to the Bobcat 21. But the opening drive ended with Ohio’s Gerald Moore slamming into tailback Bill Belton and causing a fumble.

The drive consisted of 12 plays. The Nittany Lions used 10 different formations.

Penn State scored its two touchdowns in the first half. McGloin looked off Allen Robinson, who had nine catches for 97 yards, and hit Belton for a 6-yard touchdown with three seconds left in the first quarter. Three plays after true freshman Nyeem Wartman blocked a second-quarter punt, McGloin fired a 14-yard touchdown pass to Matt Lehman.

Allowing a blocked punt was the only major gaffe by the Bobcats, who returned 15 starters from a team that went 10-4 and won a bowl game last season.

Junior quarterback Tyler Tettleton dissected Penn State’s defense, completing 31 of 41 passes for 324 yards. Penn State’s only sack belonged to redshirt freshman defensive end Deion Barnes, as Ohio’s offensive line thwarted multiple charges by veterans Jordan Hill, Sean Stanley, Michael Mauti and Gerald Hodges.

Ten Bobcats caught passes and gritty running back Beau Blankenship gained 109 yards on 31 carries. He also caught seven passes for 72 yards.

“With the dinks and dunks and the flares to the running back, it was hard for us to make any plays,” Barnes said.

Ohio, which received $850,000 for visiting Beaver Stadium, sealed its first victory over a Big Ten opponent since a 2006 triumph over Illinois when Tettleton lobbed a 5-yard touchdown pass to Donte Foster with 2:55 left. Foster caught the pass in the southeast corner of the stadium, the massive stadium’s loudest section.

“Let’s give credit to Ohio,” said Mauti, one of the Nittany Lions’ emotional leaders. “They are a good football team. They have good players. We are going to have to look at the tape and see if guys are missing gaps or not getting off blocks. We will improve on that and move forward.”

The Nittany Lions might be forced to move forward without some key players. Belton and senior cornerback Stephon Morris suffered ankle injuries, while Hodges missed time with a lower-body injury.

O’Brien revealed no details about the extent of the injuries.

The game sets the backdrop for O’Brien’s first major in-season coaching challenge. The Nittany Lions have six days to prepare for next weekend’s trip to Virginia. The Cavaliers went 8-5 last season and smacked Richmond 43-19 on Saturday.

“We have to do better offensively, we have to get the defense off the field and the defense has to make stops,” O’Brien said. “We have to coach better and it starts with me.”

Follow Guy Cipriano on Twitter@cdtguy.