Cam Newton showed glimpses Saturday night of why the Carolina Panthers made him the No. 1 pick in the NFL draft, from the strong arm that zipped the ball downfield to the mobility that bought extra moments in a collapsing pocket.

He also looked like a rookie quarterback struggling with his accuracy.

Newton led a pair of field-goal drives in his NFL debut, and Jimmy Clausen threw a touchdown pass to Greg Olsen to help the Panthers beat the New York Giants 20-10 in a preseason game.

Newton, the Heisman Trophy winner from Auburn, twice failed to get the Panthers into the end zone on promising first-half drives. But he also brought some big-play potential to the league's worst offense last season and a franchise in desperate need of a fresh start.

In fact, the loudest cheer might've come when Newton took the field less than a minute into the second quarter.

"I was just trying to go out there and first off prove to myself that I could play on this level," Newton said. "After that first little completion, I started to get the juices flowing. It was like, 'Hey, I'm in the NFL,' and I started to get a little swagger about myself."

Newton completed 8 of 19 throws for 134 yards, including a pair of completions of at least 30 yards. Newton played until early in the fourth quarter before giving way to veteran reserve Derek Anderson.

"They had me guessing out there and I know this is just the beginning of what's more to come," Newton said.

Michael Boley, who returned an interception 56 yards for a score for the Giants' only touchdown, said Newton looked "pretty comfortable."

"You saw what happened when he came into the game — he got a standing ovation," Boley said. "He's got a pretty good cannon."

The game also marked the debut of Panthers coach Ron Rivera, who replaced John Fox as the franchise begins a significant overhaul after a two-win season.

Newton took snaps from the shotgun in Auburn's spread offense, throwing for 30 touchdowns and running for 20 more in an unbeaten season that ended with the national championship. But he looked comfortable enough under center and even tried to block for David Clowney on a reverse during his first series.

His first throw was a safe one, a rollout to the right on play action for a short pass to Olsen that the tight end turned into a 10-yard gain. A few plays later, Newton found Olsen again with an on-the-button throw to the left for a 30-yard gain that set up a first-and-goal.

But Newton twice failed to connect with Brandon LaFell in the end zone, forcing Carolina to settle for a field goal. Newton also led the Panthers on a 54-yard drive in the final minute of the half, but rushed a pass against pressure and overthrew an open Armanti Edwards at the goal line to set up another field goal for a 13-10 halftime lead.

Rivera said he thought Newton was too excited near the end zone.

"Sometimes you may want to settle him down, but at the same time him being that is what makes him so special," Olsen said. "You kind of have to play both sides of the fence there. You know both (Newton and Clausen) did a great job for their first time out. We've only been at this with the whole squad for about a week now."

While Newton avoided big mistakes, the same couldn't be said of Clausen. The second-year passer heard boos from the moment his second pass hit Boley in the hands barely 2 minutes in. When the next drive ended with Clausen taking a third-down sack, some fans stopped booing long enough only to begin chants of "Cam! Cam!"

Clausen salvaged his night by finding Olsen for an 18-yard touchdown on the next possession.

New York coach Tom Coughlin didn't see any such bounceback from his offense.

"When we had that interception for the score ... you can make something really good happen for your team by just scoring again," he said. "I was very disappointed it didn't happen."

Eli Manning didn't lead a scoring drive in his five series, completing 4 of 9 passes for just 36 yards. Lawrence Tynes also missed two field goals and had another kick blocked.

"We never got into a great rhythm," Manning said. "We missed some opportunities in the passing game, and never really got anything down the field."

Notes: Carolina added an insurance score when Anderson found Kealoha Pilares for a 35-yard touchdown in the fourth. ... Tynes said his right knee seemed OK after Sean Ware rolled into his leg on a blocked field goal. ... LaFell had a 31-yard catch from Clausen on the first offensive snap. ... Backup Sage Rosenfels threw for 129 yards for the Giants.