Bartell -- the "old guy" in the secondary at age 31 -- has taken on a mentorship role with the young players in his position group.
"I've been in the league nine years now," he said. "It takes a lot of hard work and dedication to get to year nine.
"It's a short-lived career, so I just try to teach them how to be coachable, take care of their bodies, take care of finances, and make sure I'm leading by example."
With three second-year players and one rookie in his position group, Bartell -- along with veteran
Even though he is focused on winning the starting spot opposite Houston, Bartell sees this role as something that is mutually beneficial.
"If we're going to be as good a group as I think we can be, we all have to pull for one another," said Bartell. "We all recognize that this is a performance business and the best man will win the job.
"If I'm starting or if I'm backing up, I have no problem. I've been around long enough to know what this game is like and I try to tell them to prepare as if you're a starter because you're always one play away from being the starter anyway."
Bartell has high value to his young teammates, but he also has a high value to the Lions' defense because of his experience.
Under general manager Martin Mayhew, the Lions have drafted four young cornerbacks the past two years. That means Detroit has high talent in the secondary, but low experience.
Particularly at the cornerback position, experience is coveted.
"Footwork is a big thing for every cornerback," said Bartell of the techniques the Lions' young players will need to pick up. "Just being disciplined -- knowing the game of football.
"Knowing how offenses are going to attack you, knowing how to play to your strengths and rally to your weaknesses."
Bartell's experience is particularly beneficial to Greenwood considering he missed his rookie year entirely due to an abdominal tear.
"To be honest, he's the most gifted guy in the secondary," said Bartell. "Athletically, I don't think any of us stack up to him. He has a lot of talent, but he's very raw.
"So he has to get his technique down."
Bartell says things are "moving really fast" for Greenwood, who is essentially experiencing this season as a rookie.
"Hopefully things will slow down once camp starts," said Bartell. "But as far as talent level, he has it all."
Bartell categorized Bentley as talented and "eager to learn", Green as a competitor who "goes 100 miles per hour every play" and Slay as "another young, talented guy" that has a big future ahead of him.
"I haven't been around this many young, talented corners in my career," said Bartell. "So I just try to encourage them all and let them pick my brain a little bit."