Cardinals tight end Troy Niklas is only 24 and still has the boyish face that once prompted former teammate John Carlson to say the 6-foot-6, 270-pound Niklas looked “like a 12-year-old boy that swallowed a grizzly bear.”

But Niklas has been through a lot in the three years since the Cardinals drafted him in the second round out of Notre Dame, and not much of it has been positive.

He has undergone six surgical procedures. He has started only seven games. He has caught only eight passes.

It hasn’t been what Niklas or the Cardinals expected, yet Niklas is back for a fourth season, and the Cardinals remain hopeful he will fulfill his potential.

“Troy just has to stay healthy,” coach Bruce Arians said. “He was coming on like gangbusters last year. I remember (television analyst) Jon Gruden came in and said, ‘Where the hell is 87? He’s a great player.’ I said, ‘Hurt again. Bad luck.’”

Staying healthy has been a struggle for Niklas since he decided to leave Notre Dame after his junior season. Doctors at the scouting combine found Niklas had a sports hernia that required surgery.

Three days into the Cardinals’ practices that spring, Niklas suffered spiral fracture to a finger on his left hand. Another surgery.

During his rookie season, Niklas suffered two severe ankle sprains and was placed on injured reserve in November.

“Two surgeries,” Niklas said, “one to fix, one to take some hardware out.”

He played in all 16 games in 2015, and looked so good in training camp last summer that Arians was praising him publicly.

That was nice, Niklas quipped at the time, because the “coach gets my name confused with dumb motherf—-r a lot.”

Niklas entered the season as a starter and played fair, not great, in Arians’ estimation. But on the flight home from Buffalo in Week 3, Niklas noticed a clicking in his left wrist as he used his iPad to watch video of the game.

He didn’t think much of it, until doctors found damage the next day. Season over.

“Two wrist surgeries,” Niklas said. “One to fix it, one to take the hardware out.”

Niklas is healthy now, and he and Jermaine Gresham are the team’s starting tight ends. Remaining healthy is important for Niklas and the Cardinals. Niklas is in the final year of his contract, and the Cardinals don’t have much depth at the position. For both parties, 2017 would be a good time for Niklas to fulfill his potential.

“I’m thankful to be here,” Niklas said. “I appreciate coming in the building every day, more than ever. The thing about the NFL, you never know when it’s going to be over. You have to appreciate everything you have. More than anything, the injuries have helped remind me of that.”

Outside of football, this spring already has been productive for Niklas, who got married last month. Entering his fourth season with the Cardinals, Niklas is comfortable inside the locker room, too.

“It feels more like a family,” he said. “I know everyone. It just makes everything so much more enjoyable.”

Niklas insisted he doesn’t think much about earning another contract, or listen to critics who say he’s injury prone.

“It’s all about a process,” he said. “The end of that process is being a high-level tight end. I have very high expectations for myself and so do my coaches. I’m going to do my best to fulfill that.”

Note

Guard Dorian Johnson, the Cardinals’ fourth-round pick, has signed a four-year contract, the team announced Friday.

Johnson is the fifth draft pick to sign. The only two who haven’t are linebacker Haason Reddick, the first-round selection, and safety Budda Baker, taken in the second round.

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