Cam Newton had one of the greatest debut performances in NFL history on Sunday, but after the Panthers’ 28-21 loss to the Cardinals, he was unhappy.

One of the veteran leaders in the Panthers’ locker room is taking that as a good sign from the rookie quarterback.

“Cam is very disappointed,” wide receiver Steve Smith said. “I’m encouraged by that.”

Newton, who’s just a year removed from leading Auburn to a perfect season, was dejected about the loss. “The last time I lost a game was Navarro Junior College,” Newton said. “What do you want me to say, it feels great? It is not a comfortable feeling for me.”

Panthers’ Cam Newton Is Sweet In Defeat

Brushing off criticism that he could not succeed as a pro passer, Newton shredded the Arizona secondary for 422 yards and accounted for all three of the Panthers’ touchdowns. But the Cardinals took advantage of secondary and special teams breakdowns by the Panthers to claim a 28-21 victory and spoil the debut of the No. 1 draft pick.

Newton broke the record held by Peyton Manning (302) for passing yards by a rookie in Week 1 and equaled Matthew Stafford’s record total for rookies. Stafford, the No. 1 overall pick of Detroit, threw for 422 yards against Cleveland in Week 10 in 2009.