Linebacker Larry Foote celebrates the Cardinals' final fourth-down stop Monday night in an 18-17 win over the Chargers.

The problem, Bruce Arians said often in early in the 2013 season, was that his team didn't truly believe it could win.

As the Cardinals opened 2014, that was no longer a problem.

"You can see the difference, where the confidence is right now," defensive end Calais Campbell said after the Cardinals delivered a tense 18-17 win over San Diego at University of Phoenix Stadium on the back half of "Monday Night Football."

Confidence was everywhere. It came from defensive coordinator Todd Bowles, whose defense – even with a multitude of

personnel changes looked a lot like last year's stout unit – came after Chargers quarterback Philip Rivers three straight times on blitzes to get the ball back on downs.

"He said he was going to send pressure and rely on his secondary in zero coverage and put the pressure on the quarterback, make him get rid of the ball fast so he couldn't have a clean read," cornerback Patrick Peterson said. "To go zero coverage, three downs straight is unbelievable."

It came from the offense, which despite some fits and starts generated a gaudy stat sheet and more importantly a 91-yard fourth-quarter drive to score what turned out to be the game-winning touchdown.

"The last drive was something every single guy had a hand in," coach Bruce Arians said.

Maybe it shouldn't have been that close. Carson Palmer threw for 304 yards and a pair of touchdowns with no interceptions. The Cardinals (1-0) had top running back Andre Ellington playing (at less than 100 percent) and he spearheaded a running game that got to 109 yards and 4.2 yards a carry. The defense, ranked No. 1 in the NFL last year against the rush, allowed only 52 yards on the ground.

The Cards had more yards, more first downs, more time of possession.

Such is the flair for the dramatic Arians' team seems to embrace. The Cardinals were losing by five with 6:50 left with the ball at their own 9-yard line. Only an improbable 12-yard scramble by Palmer on third-and-10 got the team a first down.

By the time that drive ended, 95 total yards later (thanks to a penalty), rookie wide receiver John Brown had his first NFL touchdown on a 13-yard screen pass and the Cardinals had their lead. Sure the two-point conversion failed – the second time the offense couldn't get one – but that just meant the defense couldn't allow any points.

At the two-minute warning, the Chargers had the ball on their own 40, facing second-and-2. Three straight passes. Three straight incompletions, with veteran linebacker Larry Foote deflecting the fourth-down pass just enough for a win.

"(Bowles) puts the trust in us," safety Tony Jefferson said.

If anything tells of the difference between Arians' first two Arizona teams, it's this: The Cardinals held an 11-point fourth-quarter lead in the opener and lost by three to the Rams. This year, they overcame an 11-point fourth quarter deficit to win by one.

"I've been a part of a few teams that would have folded in that situation," center Lyle Sendlein said. "Especially around here, big primetime games haven't gone our way. For us to fight back like that, it's something to be proud of."

The big deficit wasn't only on the scoreboard. "It felt like we were down more than we were," Palmer said, and the Cardinals did catch some breaks along the way. The defense made sure that an early punt block of newcomer Drew Butler (after a blocking mistake by rookie Deone Bucannon) didn't haunt, when the Chargers could only get a field goal when getting the ball at the Arizona 17.

The Chargers (0-1), in field goal range and up 17-12 midway through the fourth quarter, lost a chance at points when a shotgun snap went through the hands of Rivers for a 14-yard loss.

"That was a killer for us," Chargers coach Mike McCoy said.

It allowed the Cardinals to create their offense-scores-defense-holds primetime finish.

Satisfaction wasn't abundant afterward, not with Bowles talking about the lull his defense had in the early third quarter and Ellington wanting to get totally healthy and Michael Floyd (who had 119 yards on five catches) seeking more offensive consistency.

But the Cardinals go into a short week and a road trip to New York with the win they wanted. That's good enough for now.

"It sets the table for us," Arians said, "to continue to build."