Last season, six different undrafted rookies suited up for the Tampa Bay Buccaneers during the regular season, many of them adopting significant roles on the team. That's a high number, but it varies only in degree from previous years, not in practice. Every year, some undrafted rookies prove they are ready to play in the NFL.

After the conclusion of the seventh round of this year's draft last Saturday night, the Buccaneers signed 14 rookies who had been passed over. Those 14 could be joined by a few more undrafted hopefuls in the next couple weeks, after the coaching staff pores over mini-camp tape of the 26 tryout players in town for the weekend.

VIEW: BUCS MINI-CAMP ROSTER

Wide receiver Adam Humphries was at One Buccaneer Place for a tryout two years ago. He subsequently got a spot on the offseason roster, a platform to prove himself in training camp and inclusion on the regular-season roster. Last year, he was the Bucs' slot receiver and he contributed 55 catches. He's proof, as were Alan Cross and Javien Elliott and four others last year, that a player's draft (or non-draft) status does not affect his chances of making the team.

What could affect those chances, however, is depth-chart need. Obviously, a thinner position group is going to offer more opportunities for unproven players to grab a spot. That's how cornerbacks Elliott and Jude Adjei-Barimah hooked on the last two years.

So where might those opportunities lie this year. Head Coach Dirk Koetter offered up a few hints, though he stressed that any player who proves worthy can make it, regardless of position.

"Well, there's opportunity everywhere," said Koetter. "If a guy's good enough, he's good enough and that's the beauty of it. From a numbers standpoint, I would think linebacker is one. Linebacker and corner are maybe two positions that we're not as deep at as some others."

Not coincidentally, cornerbacks and linebackers made up 42.9% of the Bucs' post-draft haul on Saturday night. The team added three cornerbacks – West Virginia's Maurice Fleming, Iowa's Greg Mabin and Boise State's Johnathan Moxey – and three linebackers – Mississippi State's Richie Brown, Michigan State's Riley Bullough and Arizona's Paul Magloire – via the undrafted ranks.

The linebacker position even has an open starting spot, as free agent Daryl Smith has not been re-signed. Smith started at strongside linebacker for the Buccaneers in 2016; now that spot will likely be a competition between such players as 2016 draftee Devante Bond, 2017 third-round pick Kendell Beckwith and holdovers Cameron Lynch and Adarius Glanton. Still, Brown, Bullough and Magloire can dream not only of making the team but perhaps making a quick impact on defense.

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All three of those players have strong resumes from major college programs.

"We honestly had a list that we were working down but all those guys had really good college careers," said Koetter. "That's why we want to take a look at them."

• In addition to the 26 rookies trying out this weekend, the Buccaneers also got exemptions to let three players with previous exposure to the NFL sign tryout contracts, too. They are wide receiver Riley Cooper, defensive tackle Darius Cummings and punter Cason Beatty.

Cooper and Cummings are both former Florida Gators while Beatty played for Florida State. While Beatty and Cummings haven't actually played in the league yet – they both got a shot with the Carolina Panthers last year – Cooper played extensively for the Eagles from 2010-15, peaking at 55 receptions in 2014.

Cooper was released by the Eagles after the 2015 season and did not catch on with a team last year. While that was disappointing and a little surprising to him, he does admit that the year out of the league did wonders for his body. The former Clearwater prep star is hoping to prove he can still produce in the NFL at the age of 29.

"It's a great opportunity and I'm sure excited about it and I'm trying to make the best of it," said Cooper. "Go out there, try to make some plays, run around and kind of spread my knowledge to maybe some of the younger guys if I can be of any help. I'm a hometown Tampa boy, so it's cool to be back.

"I just kept grinding and grinding and the opportunity is finally here and you've got to make the best of it. There's a lot of guys. There's 90 guys fighting for 53 spots and we will see how it goes. But, I'm really excited and all of the wideouts in the room that I've met so far are really good dudes."

READ: ROOKIES HIT THE GROUND RUNNING

Cooper doesn't have a spot on that 90-man roster yet but the Bucs could probably use experienced help at the receiver position. Even though they added DeSean Jackson in free agency and Chris Godwin in the draft, there should be quite a bit of competition to fill out the back half of the depth chart. Right now, those competitors include Freddie Martino, Donteea Dye, Bernard Reedy and Derel Walker.

"He's a guy that we decided to bring in, take a look at," said Koetter of Cooper. "He's an experienced guy, we committed to him before the draft that we were going to bring him in. A guy with size and experience and we're looking to increase our depth at wide receiver. Now, we did address that in the draft and free agency but we'll see how it goes. We've got eight wide outs out here working and we'll see how that carries over."

Cooper was the only one of those eight who has caught a pass in the NFL before. He was definitely the elder statesman of the group on Friday, but it didn't bother him to have to show off his skills during a camp mostly devoted to rookies.

"I don't think it's humbling, it's an honor," said Cooper. "An NFL team is giving you the chance to make their roster. I don't think it's humbling at all. I think it's just a great opportunity and like I keep telling you, you've got to make the best of it, so we will see, but I am excited."

• Thanks to a shoulder procedure he underwent in March, which he delayed in order to take part in the NFL Scouting Combine, rookie running back Jeremy McNichols could only watch as his fellow Buccaneer rookies practiced the last two days.

McNichols is targeting a return to the field prior to the start of training camp in late July. In the meantime, he's dealing with the frustration of being confined to the sidelines but making the most of the non-practice portion of the Bucs' three-day rookie mini-camp.

"It's hard just having to watch everybody, but at the same time I've just got to trust the process and get back when I can," said McNichols, a fifth-round pick out of Boise State. "It's like all mental preparation. I'm in the playbook a lot, trying to get down the plays as soon as possible, just learning."

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The shoulder rehab obviously adds a level of difficulty to his assimilation into the NFL, but McNichols has succeeded at difficult transitions before. He played wide receiver in high school and stayed at that position during his first year at Boise State before being moved into the backfield. It was clearly a good decision by the Broncos' coaching staff; McNichols succeeded current Miami Dolphins standout Jay Ajayi as the starting back and over the past two years racked up 3,980 yards from scrimmage and 53 touchdowns.

"It was difficult at first, just the physical aspect," said McNichols of that WR-to-RB switch. "You're getting hit more and it's more physical at running back than receiver. But I think me playing receiver really helped me to transition to running back, just because I feel like I can line up anywhere on the field and have an impact."

McNichols also has the support of two fellow Boise State rookies in camp, Moxey and wide receiver Thomas Sperbeck. Former Boise state star running back Doug Martin is also in town and the two will be working together soon. And Ajayi, one of McNichols' mentors isn't far away, either.

"Jay's like a big brother to me, has been since I got to Boise State," said McNichols. "He's been with me through the whole journey, still. I was just with him a couple days ago. He just says, overall, 'Make sure focus and most importantly make sure you get the playbook down. Just do what you've got to do. You're here for a reason.' That's what I learned from him."