CHARLOTTE, N.C. (AP) The Carolina Panthers problem hasn't been building big leads this season, it has been keeping them.
Four times the Panthers have led by 17 points or more in the second half, only to watch an opponent storm back. All four games the Panthers have escaped with wins, but far too often it has been too close for comfort.
Coach Ron Rivera said he's ''concerned'' about his team's struggles closing out games, but refused to dwell on it as the Panthers stepped up preparations for Sunday's NFC championship game against the Arizona Cardinals.
''I'll be honest, I get it, I understand,'' Rivera said after the Panthers nearly squandered a 31-point halftime lead last weekend but held on to beat the Seattle Seahawks 31-24 in the divisional playoffs.
''But, shoot, we won those football games and look at who we played against. If this was someone that was 2-14 that did this to us, then I'd be really concerned. But it wasn't. Am I concerned? Yeah. But are these things correctable and fixable? Most certainly. Let's stay focused on what we did - we won the football game.''
Sunday wasn't the first time the Panthers have flirted with an epic collapse.
Carolina surrendered a 17-point fourth quarter lead in Week 8 to the Indianapolis Colts, falling behind by a field goal in overtime before rallying to win 29-26.
The following week against Green Bay a 23-point fourth quarter lead dwindled to eight before Thomas Davis sealed the win with a pick in the end zone in the final two minutes.
And in December Carolina let an entire 28-point lead slip away before Cam Newton led a late drive to set up the winning field goal as time expired.
Rivera said the common denominator in those four games was facing a top-tier quarterback, referring to Wilson, Aaron Rodgers, Andrew Luck and Eli Manning.
''When you get a big lead like that, one of the things is you have to learn to not relax,'' Rivera said. ''You have to learn to continue to attack.''
Warren Moon knows how difficult it can be to maintain a huge lead.
He was the quarterback for the Houston Oilers when they squandered a 32-point lead and lost 41-38 to the Buffalo Bills in the 1992 NFL playoffs.
Moon said keeping a lead ''shouldn't be as difficult as teams make it,'' but that too often a big lead forces an aggressive team into a more conservative approach - on offense and defense.
Then teams tend to start looking at the clock, hoping to hurry it along. Moon said that is ''a real death sign.''
Moon worked as broadcaster at Sunday's Seahawks-Panthers game and noticed Carolina got away from what they were doing early in the game, particularly on defense.
''I've always said that the only thing prevent defenses do is prevent you from winning,'' Moon said. ''With Carolina, they're an aggressive team. And when you take that away and start playing zone and giving up room, that is when you start giving up big plays.''
The Cardinals have done a much better job of putting teams away after building big leads. But they did surrender a 19-point advantage against Seattle this year before coming back to win 39-32.
''As coaches, you tend to guard against the bad things that can happen and you don't want that to happen, so you've just got to keep your foot on the gas,'' Cardinals coach Bruce Arians said.
That isn't always easy to do.
''It's a fine line in keeping it wide open and also trying to call plays that are really good that also will keep the clock moving,'' Panthers offensive coordinator Mike Shula said.
Newton said too often this year the Panthers have ''let the foot off the throttle'' and lacked a killer instinct.
''Our philosophy, at times, was just to play keep-away,'' Newton said of Sunday's win.
He knows the Panthers can't afford to take the same approach if they get in a similar position Sunday against the high-powered Cardinals, who have the league's top-ranked offense.
AP Sports Writer Bob Baum in Glendale, Arizona contribute to this report.
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