Shields gets tackled after his first interception of the year.

In some circles — namely, mine — Green Bay Packers rookie cornerback Sam Shields has already been labeled a future starter with the potential to be a star.

Shields, who has tremendous speed, has improved by leaps and bounds since coming to the Packers as an undrafted free agent out of Miami, where he played the position for only one season. He’s also done an admirable job of holding down the nickel cornerback spot for the team since earning the job in training camp.

According to cornerbacks coach Joe Whitt, we haven’t seen anything yet.

“Write this down,” Whitt said. “Sam is going to be one of the top corners in this league in two years.”

No one’s ever achieved anything based solely on potential, but that’s high praise coming from someone who should know.

Shields’ progression this season has had a lot to do with his willingness to study, something he’s picked up from Whitt and cornerback Charles Woodson and something that’s paying off on game day.

“I’m still learning. But each day, I’m getting better and better. Each game, I’m getting better and better,” Shields said. “I’ve got to continue to keep doing that.

“If I keep working at staying focused, I can be that guy.”

On the season, Shields has 12 tackles and one interception.