Advocate staff photo by SCOTT THRELKELD -- Saints coach Sean Payton watches the action during rookie camp Saturday, May 17, 2014 at the Saints practice facility.

They all knew the story when they reported to Saints rookie minicamp: The team hosting them for the weekend had seven first-year players who had gone undrafted on their 53-man roster at the end of last season.

By the time they wrapped up their third practice of minicamp Saturday, this year’s crop of undrafted rookies knew two more things: what they needed to display if they wanted to follow suit — and just how difficult a proposal that is.

Even Saints coach Sean Payton admits there’s plenty his staff can’t learn about the 70 players participating at the minicamp, in which drills can’t feature live contact or pads. Coaches gauge how fast players run and whether their movements are fluid, but there’s not much meaning to derive from the limited number of snaps divvied up among the campers, some of whom the team doesn’t have much invested in.

Only six of the 70 players attending the rookie minicamp at the Saints facilities in Metairie were drafted this year. Another 17 rookies who went unpicked were among 29 participants who had a contract to be on New Orleans’ expanded preseason roster, and still more in their first year out of school were among 38 players in town on a three-day tryout that only guaranteed them travel expenses would be covered.

Nonetheless, facing similar odds, defensive end Glenn Foster, backup quarterback Ryan Griffin, tight end Josh Hill, linebacker Kevin Reddick, running back Khiry Robinson, offensive lineman Tim Lelito and cornerback Rod Sweeting convinced the Saints they deserved a roster spot last year despite never hearing their name called in the 2013 draft.

How’d they do it? According to Saints running backs coach Dan Roushar, by promptly mastering their assignments and not repeating errors despite their lack of pro experience.

“They might come out in the morning practice and make a mistake or two,” Roushar said. “And yet they had the ability to come back in an afternoon, repeat ... practice and fix those problems that just occurred. You see learning, and you see growth right off the bat, and so that leads you to believe they have the ability to grow in your system.”

Payton for his part singled out the importance of the “mental element to the weekend.”

To some, that mental element requires executing plays from systems they were never exposed to in school.

Cornerback Brian Dixon intercepted six passes in his final two seasons at Northwest Missouri State, and before that he was an All-American at Joliet Junior College before the Illinois school canceled its program. But in Dixon’s first few practices since signing an undrafted free-agent contract, defensive coordinator Rob Ryan and secondary coach Wesley McGriff have tasked him with lining up in formations he had only become acquainted with moments before.

“They’re teaching me different schemes I never learned in college,” he said. “I appreciate the predicament I’m in right now.”

At least defensive end George Uko spent his final year at Southern California before signing with the Saints as an undrafted rookie playing for defensive coordinator Clancy Pendergast, who coached in the NFL from 1996 to 2009 and was a defensive coordinator for the last six of those seasons.

Uko’s familiar with most of the concepts Ryan and defensive line coach Bill Johnson had invoked at the minicamp. But the speed at which Payton and his assistants expect players to fully grasp their orders takes adjusting.

“Making the same mistake twice doesn’t fly here,” Uko said.

But, in one respect, minicamp has been exactly as newcomers were told it would be. The Saints often mention that they judge and instruct prospects at their facility without regard to how they were acquired, and Uko confirmed New Orleans’ No. 1 pick in 2014 — wide receiver Brandin Cooks — has not been given any extra considerations over his lesser-touted counterparts.

“They don’t treat Brandin Cooks or (fifth-round selection) Ronald Powell or any other player they drafted different than they treat me,” Uko said. “That’s what you enjoy.”

Rookie Timothy Flanders enjoyed one other reality: The Saints offense in 2013 made room for undrafted players from smaller schools, such as Robinson (West Texas A&M), running back Travaris Cadet (Appalachian State), Lelito (Grand Valley State) and Hill (Idaho State).

That was primarily why Flanders elected to sign with the Saints when he went undrafted, and they all proved how players like him could latch onto a team that has been to the playoffs four of the past five seasons.

“I’m trying to gain as much knowledge of the playbook as I can,” said Flanders, who rolled up 5,664 rushing yards and 66 touchdowns from 2010-13 to help Sam Houston State win a pair of Southland Conference titles and appear in two FCS title games. “That’s one thing that can separate you from another player (this weekend).”