JACKSONVILLE – Myles Jack didn't say Tuesday was easy. Not even close.

But it was exciting, and when the Jaguars' rookie linebacker spoke to the media following his first NFL practice late Tuesday morning, that was his focus.

Jack, a linebacker from UCLA and the Jaguars' second-round selection in the 2016 NFL Draft, said he struggled with the heat in the team's first practice of 2016 minicamp Tuesday. That was perhaps his biggest takeaway.

He also said it was good to practice. At last.

Actually, it was really, really good.

"It was fun," Jack said following a two-hour non-padded, non-contact practice at the team's practice fields adjacent to EverBank Field. "I definitely have to get in shape and get more reps, but it was just fun playing football again.

"I really enjoyed it. I definitely made a lot of mistakes and I'll learn from them, but it was good being with the team and getting acclimated."

Jaguars Head Coach Gus Bradley called Jack's first practice with the team "good."

"I talked to him right in the middle," Bradley said. "We had a cool zone and he said, 'Yes, I am back – it is good to finally be back on the field.' I give him credit. He did a good job picking up the defense during that timeframe and he is going to be here this summer so that is going to be good."

Jack hadn't practiced since sustaining a knee injury early last fall. He worked out for teams before the NFL Draft and participated in the Jaguars' rookie orientation in early May, but did not participate in the Jaguars' offseason program until Tuesday because of an NFL rule prohibiting rookies from practicing in the offseason program until their schools finish spring classes.

Jack in accordance with NFL rules received information from Jaguars coaches that he could review on his iPad. He also said he worked out daily in Arizona during his time away.

"You can really only prepare mentally," Jack said. "You can't prepare physically for an NFL practice if you haven't done it before. I tried to be involved as much as I possibly could. I did the best I possibly could and now I have to take it to the next level."

Jack said there was a limit to how much he could prepare mentally in the last month and a half.

"There's not a whole lot you can do being away," he said. "It's definitely tough. I could kind of get in the playbook every once in a while, but it wasn't like I was really there. It was tough, but I'll get right."

Jack, who said he will remain in Jacksonville working out at EverBank following minicamp, said while other rookies met veteran players in early May as of Tuesday he was still learning people's names.

 "It's like first day of school," he said. "I don't know where to sit in the team meeting room.

Jack said while little surprised him about his first practice the Florida heat and humidity was absolutely an issue – and he said the NFL is certainly different from college.

"You're moving to a new level," he said. "Obviously I'm in Florida instead of California so I have to get used to the heat. Everybody's bigger, faster, stronger so there's a lot going on."

Jack began practice in long sleeves and quickly switched to no sleeves.

"I was trying to be like the other linebackers," he said with a smile. "I learned you have to work your way up to that. I learned it as soon as I came out on the field. I'm going to be a sleeveless guy until I get acclimated."

The Jaguars limited Jack's reps in Tuesday's practice to allow him to get acclimated to the heat and to the defensive calls. He continued to work at middle linebacker, where he during the team's rookie orientation in early May.

Jack is considered one of the faster linebackers to enter the NFL Draft in recent memory. He said the Jaguars' veterans linebackers advised him to focus on using that speed his first day.

"If all else fails, run and get to the ball," Jack said they told him. "You can fix the other stuff, but you're effort has to be there."

Jack had been projected as a potential Top 5 selection before concerns over last season's knee injury caused him to slip to the second round. The knee is considered more of a long-term issue than short-term and Jack has been cleared to participate in minicamp.

"I felt good," he said. "It's really just conditioning. I've got to get in shape and get acclimated. It's a new tempo. There's a lot going on mentally. It's a whole new game. The knee, I thought was fine. I felt good out there playing."