Skyler Gill-Howard entered Detroit Lions training camp as a sixth-round rookie trying to earn a place in one of the deepest position groups on the roster. By the end of the preseason, he may have become something much more important: a player Dan Campbell and Brad Holmes can no longer afford to cut.Gill-Howard delivered one final statement during Detroits 25-16 preseason victory over Indianapolis on Saturday, recording two tackles, one sack and two quarterback hits while again creating problems from the interior of Detroits defensive front.One performance does not earn an NFL roster spot, but an entire month of making yourself increasingly difficult to ignore certainly can.Gill-Howard Saved His Best Finish for LastThe play that will probably stick with coaches came on third down against Indianapolis, when Gill-Howard worked his way into the backfield and dropped quarterback Anthony Richardson for a five-yard loss, ending the Colts possession and getting Detroits defense off the field.It was officially Gill-Howards first sack of the preseason, but it was hardly some random flash from a player who had been quiet for the previous month. He had already been steadily creating pressure and disruption throughout August, including two quarterback hits in Detroits preseason opener against Cincinnati.That performance was enough for Campbell to single him out afterward.Hes another one of these players for a young guy who is very conscientious and he has a serious approach about him. You dont have to tell him something five times. You tell him once and hes got it and he locks in, Campbell said.That is meaningful praise for any rookie. For a sixth-round defensive tackle fighting for one of Detroits final roster positions, it carries even more weight.Campbell Has Already Explained Why Detroit Likes HimGill-Howard is not the prototype physically. At roughly 6-foot and 280 pounds, he is smaller than many NFL interior defensive linemen, and Detroit knew that when it selected him 205th overall out of Texas Tech.The Lions also knew exactly what traits made him intriguing.Quickness. Leverage. Violence. Motor.Campbell has repeatedly noticed all four.After Gill-Howard created more pressure against Washington, Campbell offered perhaps his clearest explanation of why the rookie has continued climbing.Sun Bleach just continues to make plays. He does it at practice. You can feel him out there, you know, and he just is relentless. He plays snap to whistle, and hes all out. And hes got to be right, you know he does, because hes not a huge guy. But he knows who he is and he knows how he has to play. He plays with high effort, and hes crafty, man. Hes explosive and hes violent, Campbell said.There is a lot packed into that answer. Campbell acknowledged the size limitation, then immediately explained why Gill-Howard has been able to overcome it. That is not developmental-project language. It sounds much closer to a description of someone the coaching staff believes can actually help.Gill-Howard Has Been Building This Case All SummerDetroits defensive-line competition was already one of the most difficult roster battles on the team, and Gill-Howards final preseason performance only made the numbers tighter.Aidan Hutchinson, Alim McNeill, Tyleik Williams, D.J. Wonnum and Derrick Moore are obvious roster locks. Tyler Lacy has played an important role, while Ahmed Hassanein has put together an impressive summer. Then comes the group fighting over the final few spots, including Gill-Howard, Chris Smith, Levi Onwuzurike, Mekhi Wingo, Ben Stille, Eric ONeill and others.There is no painless answer.Detroits remaining roster battles were already shaping up to be brutal, especially along the defensive line. Gill-Howard has simply made that decision harder.His rise has not been limited to preseason games, either. He received increased first-team work late in training camp, another important signal considering where he began the summer. Coaches do not generally move sixth-round rookies upward on the depth chart by accident.Detroits final 53-man roster prediction entering the preseason finale already had Gill-Howard making the team. Saturday only strengthened the case.His Background Makes the Rise Even More InterestingGill-Howards path to Detroit was anything but conventional. He began his college career at Division II Upper Iowa before transferring to Northern Illinois, where his only FBS opportunity required him to change positions and become a defensive tackle after previously working as a linebacker.He eventually developed into a team captain at Northern Illinois before transferring to Texas Tech for his final college season. In other words, Gill-Howard has only been playing defensive line for a handful of years.That matters when projecting what he could become.Gill-Howard arrived in Detroit as a 23-year-old rookie who was still relatively new to the position, yet he has already created consistent disruption against NFL competition. The Lions may not simply be evaluating what he is right now. They may also be thinking about what he could become with another year or two of development.The Roster Math Is Still BrutalNone of this means Detroit suddenly has an easy decision.Quite the opposite.Gill-Howards emergence makes somebody elses situation considerably more uncomfortable. Campbell and Holmes could realistically keep nine or even 10 defensive linemen depending on how they categorize players who can align at multiple spots, but every extra defensive lineman means one fewer receiver, cornerback, linebacker or offensive lineman.That is where roster construction becomes different from simply identifying the best 53 football players.Still, Gill-Howard provides exactly the kind of traits coaches covet near the bottom of a depth chart. He can rush from inside, disrupt running plays and keep working when his initial move fails. He has consistently created negative plays throughout August.There is also the waiver risk. Gill-Howard is young, inexpensive and under team control, which makes him exactly the kind of developmental defensive lineman another organization could be willing to claim rather than allow Detroit to stash him on the practice squad.That has to be part of Holmes calculation Sunday.Gill-Howard Did Everything He CouldRoster-bubble players do not control the numbers. They cannot decide how many defensive tackles a team keeps or which injuries force the front office to protect another position.All they can do is make the decision uncomfortable.Gill-Howard did that.He flashed against Cincinnati, created more disruption against Washington and then finished the preseason with a sack and two quarterback hits against Indianapolis. The Lions drafted him 205th overall four months ago, but by Sunday evening, draft position probably will not matter much.The film will.And Gill-Howard has spent the last month giving Detroit more and more reasons to keep watching it.At some point, a roster-bubble player stops trying to win a job and starts forcing the organization to explain why it would let him go.Gill-Howard may have reached that point.