Cardinals quarterback Carson Palmer doesn't feel like the deep ball is essential to offensive success.

There is a play-caller's vision, and then there is reality. Lining them up has always been the challenge.

In 2015, coach Bruce Arians' vertical passing game philosophy was executed to perfection by quarterback Carson Palmer and the Cardinals' receivers.

Palmer led the NFL in yards per attempt (8.7), while Larry Fitzgerald, John Brown and Michael Floyd combined for 3,067 receiving yards and 22 touchdowns. Spurred by a coach with the famed no-risk-it, no biscuit mentality, everyone had plenty to eat.

In 2016, with that identical quartet returning, there was every reason to think it would click again. But the Cardinals' deep-ball effectiveness cratered, and Palmer dropped to 17th in the NFL in yards per attempt (7.1).

While Fitzgerald was his normal reliable self, Brown was dogged all season by injuries -- a concussion, complications from the sickle-cell trait and a cyst on his spine. Floyd was healthy, but maddeningly inconsistent, before getting released on Dec. 14 after a driving under the influence arrest.

Arians summed up the deep-ball woes succinctly.

"John Brown couldn't run and Michael Floyd dropped about five," Arians said. "That's easy."

As the season wore on-- and as it became clear the receivers weren't producing as expected, the line wasn't keeping Palmer clean and safeties were staying deep – the Cardinals' passing attack shifted.  

Palmer became more selective taking his shots, finishing the season with fewer pass attempts of 20-plus yards than in any other year of his Cardinals career, per Pro Football Focus.

To illustrate the change: In 2015, Palmer finished ahead of Tom Brady and Drew Brees with 15 completed passes of 40 yards or more. In 2016, he was behind Tyrod Taylor and Alex Smith with six.

Even so, it didn't necessarily mean the end of high-powered performances, as the Cardinals had three of their four highest point totals -- 44 against the Rams; 41 against the Saints and 34 against the Seahawks -- in the final three weeks of the season. The difference came in the distribution of completions.

In the final 10 games of the season, running back David Johnson averaged 3.2 more targets, 2.7 more catches and 17.4 more yards per game than in the first six. Tight end Jermaine Gresham averaged 3.4 more targets, 2.1 more catches and 23.4 more yards per game over the same timeframe.

"I think we got better as the season went on, especially the check-down stuff, the shorter and intermediate throws," Palmer said. "We got more comfortable with that as a group."

As Johnson continued to put defenders on skates in the open field, Palmer found him often.

"I started getting more and more comfortable," Johnson said. "Me and him got more and more in rhythm, learning each other's strengths."

The Cardinals' passing game identity for 2017 will soon form, but now there are two sides to the debate.

There's a strong case for the return of the deep shots, as the offensive line is healthy again, Brown feels back to full speed, and J.J. Nelson emerged late in the year as a dynamic big-play threat. Plus, the Cardinals are confident Palmer can still sling it.

"He has the best deep ball I've ever seen," Nelson said. "I love catching them. With B.A. loving those type of plays, I'm good here, you know what I'm saying?"

The case for conservatism is centered on Johnson, who has transformed into an elite back. There are worse options than handing or tossing him the ball and waiting to see what comes next.

It also helps Palmer, who can avoid hits by getting the ball out quickly.

"We've got so much good stuff built for underneath coverage that I don't think (the deep ball) is vital," Palmer said. "I think it definitely helps, and it's nice. It makes 15-play drives two-play drives. Those are nice. But we have so much good stuff built underneath for Larry and for David. Andre (Ellington) has done some really nice things underneath. Jermaine's done some really nice things. We have a lot of really good offense that isn't throwing the ball 40 yards down the field."

The identity could be determined gradually. Most passing plays have both deep shots and underneath options built in. Arians and Palmer may have an idea on progressions, but that can change based on coverage.

"We do whatever the defense dictates for us," Arians said.

At his core, though, Arians is a risk-taker. While the Cardinals could choose the short and intermediate game, the aggressive vertical philosophy has always seemed the most optimal for this coach and quarterback pairing.

Nelson wants the deep ball to make its triumphant return in 2017. He salivates at the thought of streaking past defenses and looking up for the perfect spiral Palmer often delivers.

"Man, it's pretty," Nelson said. "He doesn't hesitate. He throws it up there and lets you go get it. With Carson resting a few days, his arm's been looking great. We've been running great routes.  Hopefully it translates to the season."