TEMPE, Ariz. -- The secret to the Arizona Cardinals' offensive success during coach Bruce Arians' first three seasons has been staring opponents right in the face.

This year, however, the opponents have smartened up. Defenses are taking away the deep ball by using more defensive backs more often, if we take a look with the help of ESPN Stats & Information.

Of the Cardinals' 276 offensive snaps this season, 168 have been passes. Of those, the Cardinals have faced nickel coverage on 113 plays, dime on 63 plays, quarter on 23 plays and eight or more defensive backs on three plays. And of those defenses have been effective.

Arizona's quarterbacks have been completing less than 60 percent of their passes against those coverages and have thrown just two touchdown passes plus six interceptions while getting sacked nine times. When facing those coverages, Carson Palmer and Drew Stanton have had the most success against quarter coverage (seven or more defensive backs), completing 59.1 percent of their passes. But they haven't thrown a touchdown while tossing three interceptions.

Larry Fitzgerald and the Cardinals are facing more heavily loaded secondaries this season compared to last. AP Photo/Ross D. Franklin

"If you look at us, the one thing you want to take away from us is our big shots," wide receiver Larry Fitzgerald said. "Any logical defensive coordinator would see that. We like our chunk plays, and when they present [themselves] we still have to take them, and that's just who we are. But teams are going to make us sustain drives and make us play six, seven, eight, nine, 10 plays."

The defensive coordinators Arizona has faced this season, with the exception of the Tampa Bay Buccaneers' Mike Smith, have figured out the Cards' offense. Tampa Bay is the only team the Cardinals have defeated this season.

Arizona (1-3) is facing more heavily loaded secondaries this season compared to last, when the Cardinals set franchise records for points, touchdowns, touchdown passes, total net yards, first downs and passing first downs. On top of that, Palmer set a career record for yards and touchdowns thrown.

The Buffalo Bills used six or more defensive backs on 34 defensive snaps, compared to the Bucs, who used that many just five times.

Arizona has seen nickel defenses on an average of 35.5 plays per game this season, compared to 27.8 last year. Defenses are also playing dime more, averaging 16.3 plays per game in 2016 compared to 10.1 in 2015. Even quarter coverage is being played more this year, with Arizona seeing it six times per game on average compared to 3.5 last season. And in 2015, not one team sent out eight defensive backs against the Cardinals. The Los Angeles Rams did it twice Sunday and Buffalo did it once in Week 3.

Last week against Los Angeles, Arizona tried six passes that traveled at least 20 yards in the air and was able to complete two of them. For the season, the Cardinals are completing 31.8 percent of those passes -- down from 37.6 percent last year.

"Last week, the Rams' safeties, they're 20 yards deep," Fitzgerald said. "Even in their two-high looks and their single-high looks, they're deep, so even if you have something that's going deep, those guys are able to make plays.

"You have to make plays when you're underneath, and guys have to break tackles and make those short gains [into] big gains, and hopefully the safeties will start coming up and we'll make some plays down the field."

But Arians and offensive coordinator Harold Goodwin seem to differ a bit on their mindsets of how to approach the deep ball, which has become a staple of the Cards' offense under the 64-year-old Arians. He doesn't want to see Palmer check down when a bomb is an option. Goodwin wants the offense to take what it's given.

Said Arians: "The deep ball is there, just throw it a little bit further."

Said Goodwin: "Just be patient and take what they give you. Sometimes the home run's there, sometimes it's not. A lot lately, it's not here."