INDIANAPOLIS -- Indianapolis Colts linebacker Darius Leonard doesn't carry himself as somebody who says, "I told you so."

But it would be totally understandable if Leonard gets out of his comfort zone and does that at some point this season to the NCAA Division I schools who didn't want to wait for his test scores after signing day and those who snickered at the Colts for using a second-round pick on the former Football Championship Subdivision player.

Leonard, an instant starter shortly after being drafted, put on the type of defensive performance that hasn't been seen from a Colts linebacker in almost seven years when he had 18 tackles, a sack and a forced fumble in their 21-9 win against Washington on Sunday.

Linebacker Darius Leonard (53) has made a good impression on his teammates: "He approaches the game with a veteran mentality, not a rookie mentality," safety Matthias Farley said. AP Photo/Carolyn Kaster

The best player on the field Sunday wasn't Andrew Luck or Adrian Peterson.

It was Darius Leonard.

"A star in the making," veteran defensive lineman Al Woods bluntly said. "Just a guy that comes to work every single day. He takes the good with the bad. Takes the coaching, he talks to the older cats, he always tells me to remind him about his alignment. He does a good job with everything. Everything you want out of a young player."

One of the first things Chris Ballard did when he became general manager of the Colts in January 2017 was clean out the old and slow defensive players put together by the previous regime and replace them with younger, faster and tougher players.

Part of that process was finding a core group of players to build around. Safety Malik Hooker, the team's first-round pick in 2017, was one of those players. And it's pretty safe to say Leonard -- as of now -- is another one of those players. Leonard's 18 tackles were the most by a Colts defender since Kavell Conner had 18 on Oct. 3, 2011, and the most by an Indianapolis rookie since 1994.

"I remember Chris Ballard talking about him and having his eyes on him in the draft," Colts coach Frank Reich said. "Not just talking about this guy's playmaking ability, his athletic ability, but the kind of football character we want on this team. Man, what a day."

Leonard didn't just suddenly arrive Sunday. He had been showing off his athleticism and football instincts since he arrived. He was the first player to intercept Luck during training camp, and it came on athletic play when he went up and took the ball from tight end Erik Swoope.

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The difference between then and now is that Leonard's performance was in a real game and with all eyes on a defense that was supposed to have issues against Adrian Peterson and the Washington offense.

Speaking of Peterson, Leonard said his favorite play was his first one-on-one tackle on the running back.

"I watched Adrian Peterson growing up," Leonard said. "I had an AP jersey."

The Colts aren't simply telling Leonard to go out and make tackles and be a difference-maker on the field. That's only part of the equation for him. He's also responsible for wearing the helmet transmitter to get calls and make sure everybody is lined up right.

It's difficult enough for a veteran to do it, let alone for a player who at this time last year was playing against the likes of Norfolk State University while attending South Carolina State University. Leonard didn't run from the added responsibilities, he's embraced it -- even when the transmitter stopped working during part of the game Sunday.

"It's not hard, just going in and try to get everybody together and make the calls. Rookie, vet, anybody can do it," Leonard said. "I looked at it as a challenge, and I'm always sup for a challenge -- kind of put of my right foot forward and kept it going."

Ballard probably couldn’t have scripted his early draft picks any better. With the No. 6 pick he chose guard Quenton Nelson over Roquan Smith, who was called the best linebacker in the draft, and then Ballard was able to get a possible cornerstone of the defense in Leonard with the No. 36 overall pick.

"He's very mature and poised," safety Matthias Farley said. "He approaches the game with a veteran mentality, not a rookie mentality. He approaches it like a pro. Doesn't make the same mistake twice and he's eager to get better. His trajectory is very, very high and he's balling so far."