Riley Patterson is a rookie. He's a kicker. He wasn't drafted. He spent the first 15 days of Vikings training camp nursing an injured left foot while on the Physically Unable to Perform list. And, oh yeah, he works for Mike Zimmer, an old-school coach not known for being patient with kickers.

"Yeah," said Patterson, "being a rookie, it felt like I was in that training room forever trying to get better."

With his plant foot now healed, Patterson has three practices on his NFL resume. Friday, he said he, "feels awesome." Saturday, he began the team's place-kicking competition, making field goals from 36 and 49 yards as Greg Joseph went before him and was good from 35 and 47 yards.

Patterson and Joseph — a journeyman who's played 16 NFL games, none since 2019 – were getting their first look at U.S. Bank Stadium as a smattering of fans watched. Whether one of them has the mental fortitude to repeat Saturday's success when the place is packed and the real pressure is on remains to be seen.

Zimmer, however, is willing, for now at least, to let these two greenhorns slug it out. And, yes, Zim, for now at least, seems OK with the possibility of naming a 22-year-old undrafted rookie as his kicker.

"That's up to [Patterson]," Zimmer said. "Everybody says I don't like rookies. I like rookies. If they're the best players, I want them to play."

Three years ago, a rookie named Daniel Carlson was the best kicker. Very quickly, he was not.

Drafted higher than any other kicker in team history, the fifth-round pick aced Week 1. Week 2 at Lambeau Field will live in infamy in Vikings lore.

Carlson attempted three field goals, striking out from 48, 49 and 35 yards. He missed the latter two in overtime, including the 35-yarder with 4 seconds left in a 29-29 tie.

"Yeah," Patterson said. "I heard about that. Job security is tough for a kicker in this league."

Zimmer whacked Carlson the next morning. It seemed to all to be the right move at the time.

History, of course, has been much kinder to Carlson in that coach-kicker annulment. Carlson hooked on with the Raiders that year and made 16 of 17 field goals. Last year, he made 33 of 35 for the Raiders while Dan Bailey lost his job making 15 of 22 field goals and 37 of 43 PATs for the Vikings.

Patterson thought he might be drafted after leaving Memphis ranked second in school history in points (432), second in field goal accuracy (77.1), fourth in field goals made (64) and tied for first in longest field goal made (56 yards). He also nailed that game-winning 47-yarder to beat Houston 30-27 as time expired in a December game.

"But this couldn't have worked out any better," he said. "The Vikings are exactly my best opportunity."

Part of that, frankly, is Joseph's inexperience. The Vikings are his sixth team in four years. He has kicked for only two of them, making 17 of 20 field goal attempts and 25 of 29 PATs with the Browns in 2018 and 9 of 9 PATs in two games with the Titans in 2019.

"It's supposed to be an open competition," Patterson said. "That's all I want."

Only one team drafted a kicker this year. The Bengals took Florida's Evan McPherson in the fifth round. He's expected to be the opening-day kicker when the Vikings visit on Sept. 12.

Eight more kickers were signed as undrafted free agents. According to spotrac.com, Patterson's $20,000 guarantee from the Vikings ranks second behind the $28,000 the Jets gave SMU's Chris Naggar. Naggar is competing with Matt Ammendola, a 2020 undrafted rookie the Jets signed after releasing Sam Ficken on July 31.

The Chargers also are leaning toward an undrafted rookie – Pittsburgh's Alex Kessman, who set an NCAA record by making 66.7 percent of his field goals from 50-plus yards.

"It's very scary if you let yourself sit around thinking about job security as a rookie," Patterson said. "I just got out of college. I need a job. But you just got to be present, be where your feet are."

So did Zim whacking Carlson two games into his rookie season give you any hesitation in signing with the Vikings?

"No," he said with a smile. "No. I haven't talked to Coach Zimmer too much. He's got 90 other guys he's focusing on. As a specialist, I think you find your worth in how easy you are to maintain. If you're a kicker, do your job quietly and do not be causing a ruckus."