TEMPE, Ariz. — From undrafted rookie free agent to starting safety on a team with playoff aspirations in a must-win game, such is the life of Tony Jefferson.

“I’m basically just like ‘it’s about time’ for me, that’s just how I feel,” Jefferson said of the opportunity that’s in front of him. “I’m ready to go, I’m fired up.”

It’s been a bit of a journey for Jefferson from draft day disappointment to now, and he would likely not be getting this chance had it not been for injuries to some of his teammates. It’s the brutal truth of the NFL, though, that sometimes it takes someone’s misfortune for someone else to get an opportunity to make an impact.

For Jefferson, it took both Tyrann Mathieu and Rashad Johnson going down to get his crack in the lineup. So now he, with all of 20 tackles and little experience under his belt, will play an important role in a must-win game.

“I’m so excited,” Jefferson said. “Not to put anything against Rashad — if anything I want him to be healthy, but when my opportunity is here, it’s time for me to do what I’ve got to do.”

Cardinals coach Bruce Arians admitted Jefferson does not have enough experience for the role, but added that the only way to get experience is to play, and it’s worth noting that Jefferson did get a start in Week 2 against the Detroit Lions. He recorded three tackles that afternoon. And just last week, his pressure on Titans quarterback Ryan Fitzpatrick in overtime led to an errant throw that was picked off by Antoine Cason.

“He’s been a playmaker everywhere he’s been,” the coach said. “Every time he’s had an opportunity with us, he’s made plays. He jumped in the other night and basically won the game because he forced the interception.”

But it’s getting the opportunity that hasn’t come easy for Jefferson.

A first-team All-Big 12 selection as a junior at Oklahoma after leading the Sooners with 119 tackles — 3.5 of which were for loss — with two interceptions and three passes defensed, Jefferson did not hear his name called on any of the draft’s three days. Between Eric Fisher, who went first, and Justice Cunningham, who went last, a total of 254 players were selected. None of them, though, were Jefferson.

“Draft day was, that was a terrible day for me, personally,” Jefferson said. “A guy who you thought was going to get picked second day and second or third round, end up not getting picked at all was rough. But I fought my way through and I think I showed that I can fight through adversity.

“Look where I am now.”

The one benefit to going undrafted was that Jefferson could pick where he would sign, and he said he chose the Cardinals because of the talent on the roster and what the team already had at his position.

But now the position is his, and he has to find a way to be the “next man up” after playing sparingly for most of the season.

“It is what it is, whether it’s tough or not, you’ve got to be tougher,” he said. “This is a ‘show me what you’ve got’ game, especially for me.”

Jefferson pointed to teammate Antoine Cason, who stepped in last week against the Titans and produced three key turnovers, as someone who was able to do what he’s hoping to accomplish this week: come up big for a team that is suddenly relying on him.

It’s a lot of pressure for a young player, but that’s life in this sport.

“You’ve got to just be mindful, you know, you’re a football player, you belong here,” he said, adding it’s about self-motivation and understand there will be mistakes and room to improve.

Because though there are bound to be ups and downs, he would not be in the game if the coaching staff didn’t have any confidence in his abilities.

“I’m comfortable with Tony,” defensive coordinator Todd Bowles said. “He played early in the year when Rashad and Ty weren’t around. It’s not like he was playing bad, he was just behind two good ball players. I’m very comfortable in Tony.”

Now it’s up to Jefferson to validate that faith. Though his role is new, the sport he’s playing is not. And at the end of the day, that’s an important fact to remember.

“Just know that it’s football, regardless of yes, you’re going against the best players in the world,” he said. “But you belong here; you’re here for a reason.”

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