Brandon Coleman finds himself on the cusp of a big moment.

Coleman has been in the NFL for a full year; he spent last year on the Saints’ practice squad.

When he takes the field against Arizona on Sunday, he’ll feel a little like a rookie again. Coleman, who has never played in an NFL game, enters the season opener against the Cardinals as the Saints’ likely No. 3 receiver, a key cog in an offense that underwent major changes at the skill positions.

Coleman won’t have much time to reflect on how far he’s come since last season.

“This is going to be my first time going around at it, so I am treating it like (a rookie), but I can’t have those butterflies,” Coleman said.

“Once I get out there and get my feet wet, everything will just start flowing for me.”

For Coleman, the preseason finale against Green Bay offered a big jolt of confidence.

Coleman has been impressive in practices all offseason, working the middle and the soft areas behind the zones well throughout training camp and slowly establishing himself as the frontrunner to emerge as Drew Brees’ No. 3 receiver behind Marques Colston and Brandin Cooks.

Up until the Green Bay game, though, Coleman hadn’t been able to carry it over into the game.

All it took was one catch. On the first play of the final preseason game, Coleman beat Green Bay’s first-round pick, Damarious Randall, on a go route down the right sideline and hauled in a beautiful deep ball for a 45-yard gain.

Coleman finally had the big catch he’d been waiting to grab. Buoyed by the big play, Coleman finished the Packers game with four catches for 82 yards, demonstrating everything the Saints have seen on the practice field all summer long.

“I’ve done it in practices,” Coleman said. “It just needed to carry over.”

Now Coleman has to prove himself again.

New Orleans decided to go all in with Coleman and Willie Snead. During Sean Payton’s time in New Orleans, the Saints have always gone with five or six receivers, depending on how many options they had at the time.

Payton and the rest of the coaching staff decided to stick with four this time. Coleman and Snead will not be eased into a role; the two former undrafted free agents have to hit the ground running.

Their performance in the preseason convinced the Saints they could wait to add a fifth receiver to the active roster.

“We discussed receivers five and six, and even receivers five, six and seven based on how we had them graded,” Payton said. “We will kind of see how that goes, but we felt that these four guys certainly were decisions that we were settled on.”

Coleman’s role, like nearly everybody’s at this point in the season other than Cooks and Colston, remains a little unclear.

But Brees believes that’s to be expected as the season-opener looms, correctly pointing out that the offense still has some growing to do.

“I think, at times, it takes you a couple of games to see where certain guys start to fit in, certain schemes start to fit into what you are doing,” Brees said.

“You begin to see this man get really good at some things, and maybe we need to fine-tune and work on some other things.”

New Orleans will get a chance to test Coleman against the NFL’s best right away.

Arizona’s secondary is one of the best in the game, flush with talent in All-Pro cornerback Patrick Peterson, playmaking safety Tyrann Mathieu and a deep, talented supporting cast that can give opposing wide receivers fits.

Coleman can’t wait. This is his chance to confirm he belongs.

“I’m excited,” Coleman said. “I love to compete.

“This is an opportunity for me to do that.”