It seems like forever ago to Glover Quin, 31, but he began his professional career as a cornerback out of New Mexico in 2009, after Houston selected him in the fourth round of the NFL Draft.
Quin saw action in 15 games as a rookie cornerback, and ended up starting 12 of those his first season.
He started all 16 games at cornerback the following season before eventually making a switch to free safety, so Quin knows exactly what's in store for new Lions cornerbacks Teez Tabor and Jamal Agnew.
"It's difficult," Quin said of playing cornerback as a rookie. "For one, you're trying to obviously understand the scheme, and on top of that you're having to cover the fastest, best athletes on the field in some of these wide receivers. It's definitely tough."
Cornerback is already one of the most difficult positions to play in football. The adjustment that first-year players have to undertake from the college game to the NFL makes it even more difficult. Not just from a rules standpoint, where corners aren't allowed the same freedoms in terms of contact and use of hands in the NFL as they are in college, but the consistent speed at the NFL level can take some getting used to.
In college, these cornerbacks would face an elite-level NFL receiver maybe two or three times a year depending on which conference they played in. Sometimes it was just once a year. In the NFL, it's 16 weeks of world-class speed or elite-level athleticism at the receiver position.
"You get to the point where you can't always just rely on ability," Quin said. "You have to understand your techniques, understand where your help is, understand the scheme and the plays you're expected to make. Understand your responsibility and it takes time."
Even Lions top cornerback Darius Slay can attest to that. He was in and out of the starting lineup as a rookie as it took time for him to adjust to the pro game after being a starter at Mississippi State just one season. Slay didn't become a full-time starter for the Lions until his second season in Detroit.
He's since blossomed into one of the top young cornerbacks in the NFL, but that wasn't always the forecast for him. It shows how difficult playing that position really is for rookies.
"It takes time for those guys to get those reps mentally, get those reps physically," Quin said. "Being in meetings, being in all the walkthroughs. The quicker that you can learn what you got and understand how you fit inside that scheme, the better you'll be.
"If you go out there just trying to survive on natural-born ability, it's going to be difficult, because a lot of these guys are very talented naturally and if they have better technique then a lot of times they are going to win."
Tabor is expected to come in and compete for playing time on the outside with Nevin Lawson, DJ Hayden and others, while Agnew could push Quandre Diggs for playing time in the slot.
If Tabor and Agnew are smart, they'll attach themselves to veteran leaders like Quin as soon as they get to Detroit, and try to absorb some of their knowledge.
How quickly both players adjust to this level of competition will ultimately decide how quickly we'll see either one of them on the field as rookies.