Cornerback Patrick Peterson breaks up a pass for Lions wide receiver Calvin Johnson during Sunday's 14-6 win over Detroit.

With nine wins in 10 games and a second-half shutout Sunday, the Cardinals' defense can feel good.

At least, until Wednesday or so.

"Because every week during practice, we're the worst team in the league," defensive end Frostee Rucker said with a smile following the Cards' 14-6 win over the Detroit Lions at University of Phoenix Stadium. "But that's what is good. (The coaches) keep us humbled and grounded. Our work ethic is really showing."

So too is the Cardinals' talent and, increasingly, their path toward an NFC West title. The Seahawks lost in Kansas City Friday, dropping them to 6-4 and giving the Cardinals a three-game lead in the division race over Seattle and San Francisco with six games to play. Beating the Lions (7-3) also gave the Cards essentially at least a three-game lead on every other NFC division leader (with head-to-head wins over Detroit and Philadelphia.)

The formula against Detroit was simple. In the first game of Drew Stanton's tenure as permanent starting quarterback, Stanton was excellent

early with a pair of touchdown passes to the previously quiet Michael Floyd.

That was enough for a defense that was a little salty after hearing all week about the proficiency of the Lions' No. 1–ranked defense.

"When a team can't score seven points, there's a pretty good chance you're going to come out on top," cornerback Patrick Peterson said in a prime postgame understatement.

There was no scoring in the second half. Stanton threw two interceptions – one returned inside the Arizona 20-yard line – and the Cards allowed just three points off them. Wide receiver Calvin Johnson, covered almost the whole game by Peterson, had just five catches for a mere 59 yards. Lions quarterback Matthew Stafford completed 18-of-30 passes for 183 yards, and threw an interception (to safety Rashad Johnson).  He was sacked four times.

For a team that had rallied to win three straight games in the fourth quarter, the Lions weren't in a bad spot Sunday. Except the Cardinals weren't going to allow any highlight comeback.

"We know our coach is going to lean on us," safety Tyrann Mathieu said.

The Lions had just two fourth-quarter possessions. The first started at their own 1, after the Cardinals' Justin Bethel downed a punt that initially, was called as a live ball, allowing a long Detroit return. The play was overturned, and while Detroit moved the ball out to the Arizona 47, the Cards forced a fourth down incompletion.

Arians could have tried a game-icing 53-yard field goal on the Cards' next possession, but given the way his defense had played, it was never heavily considered.

"I trust our defense to hold those things," Arians said.

He was right. Drew Butler's punt pinned the Lions at their own 11 and Detroit didn't go far. One more forced punt, and the defense's job was done.

"As a defense at this time of the season, we want it to all be on our game anyway," defensive end Calais Campbell said. "With a backup quarterback, we believe in him. We wanted to all be on our game and make his job easier."

Stanton's final three quarters weren't spectacular but enough, underscored by his laser pass to Larry Fitzgerald for 11 yards on third-and-11 just before the two-minute warning to turn the game into kneeldowns.

Stanton finished 21-of-32 throwing the ball for 306 yards, the two touchdowns and two interceptions. Ten Cardinals caught passes, helping the Cards convert eight of 14 third downs. The running game slowed as the game went on – subtracting Stanton's four kneeldowns, the Cards had 22 rushes for 50 yards – but Arians was satisfied.

"To get the early lead, I think it let everybody take a deep breath," said Stanton, who was not sacked. "At the same time, we have to find a way to sustain drives better. That's come with playing with each other more and being on the same page."

It is not easy to do it in Seattle, where the Cardinals go next. The Cardinals are 9-1 for only the second time in the history of the franchise (1948) and there is something to be said for that. Arians doesn't want to get away from the focus his team has shown thus far.

"Nothing's won. Nothing's lost," Arians said. "We could lose it all in the next four, five weeks, we could win it all in the next four, five weeks."

Getting Stanton back out and steady was a solid first step in the latter. The defense is playing better than it has all season, and that's meaningful – especially with a secondary proving it should be considered among the best in the league.

If anything, the record should push the Cardinals, rather than allowing them to ease up.

"I just tell guys, 'Don't waste this opportunity,' " linebacker Larry Foote said. "It should motivate you to keep winning, keep doing extra. Guys are buying into it. It's special to be 9-1 in this league."