MANHATTAN (TNS) — Any quarterback thinking about trying to pick on Kansas State defensive back Duke Shelley might want to consider the following words from teammate Alex Barnes:

"That’s dumb."

Barnes, K-State’s leading rusher, doesn’t usually provide free advice for opponents, but he couldn’t help himself when discussing the way Oklahoma State quarterback Taylor Cornelius targeted Shelley 11 times during a lopsided victory for the Wildcats two weeks ago.

Shelley, the sudden star of K-State’s defense, allowed just five receptions for 16 yards and finished the game with two interceptions. It was foolish for the Cowboys to challenge Shelley, and he made them pay. The Wildcats shut down Oklahoma State’s usually high-octane offense and won 31-12.

“He’s the heart and soul of that defense,” Barnes said. “That dude will definitely go make a play whenever you need a play to be made. Nobody throws to him much anymore, (or) they really shouldn’t, because he is putting up crazy numbers.”

This has turned into a breakout season for Shelley. The senior from Tucker, Ga. has made 33 tackles, successfully defended 12 passes and grabbed three interceptions. He has been at his best in K-State’s past two games, making highlight reel plays every time a questionable pass is thrown his way.

Shelley is emerging as one of the best cover corners in the Big 12, if not the nation.

“Duke has played well throughout the course of the season,” K-State coach Bill Snyder said. “I like the way he plays. I like his attitude. I like his approach to the game. I like his newly found leadership skills. I am very proud of Duke.”

Why is everything suddenly falling into place for Shelley?

It’s a good question, considering he got off to a shaky start this season against South Dakota and Mississippi State. But he has looked like a dominant player since.

His transformation coincided with his rise as a locker-room leader. K-State players have long respected Shelley, but he rarely addressed them in group settings until a last-second loss against Baylor earlier this month.

The defeat dropped the Wildcats to 2-4 and 0-3 in the Big 12. No one was happy, but no one was angrier than Shelley. So he got up in front of the team and let everyone know K-State’s season was in danger of slipping away if they didn’t come together.

K-State players on both sides of the ball listened.

“He was pretty emotional after that Baylor loss,” K-State defensive tackle Jordan Mittie said. “I don’t want to go into (everything he said), but it was good.”

Shelley played well against Baylor, making four tackles and grabbing a diving interception. Then he went out and played even better against Oklahoma State.

“That really shows a lot to have a guy be that vocal and back it up the next week,” Mittie said. “It was huge.”

He appears to have staying power.

Nothing about Shelley’s recent surge feels like a fluke. He nearly had three interceptions against the Cowboys, and none of the passes hit him in the numbers. With hands like those, he could play receiver.

“Earlier in the year, I got my hands on a couple balls that I should have had and I didn’t make the play,” Shelley said. “They ended up being pass deflections, but I should have ended up with picks on them. I am trying to make a conscious effort to catch it when I get my hands on it. I am trying to make those plays.”

It will be fascinating to see how Oklahoma and quarterback Kyler Murray handle Shelley. Coming off two strong games, and Barnes’ warning, it would be counter productive for the Sooners to try and pick on him, even with receivers like Marquise Brown and CeeDee Lamb.

Still, Shelley will do his best to create turnovers and lead.

No matter what strategy the Sooners take, he will remain the defensive playmaker teammates look to for inspiration.

“These last couple weeks he has been very vocal and done more than just put his play and actions on the field,” defensive tackle Trey Dishon said. “That’s a big step. It shows that he cares. A lot of guys have seen that and reacted to it.”