Brent Venables is overqualified.

Anyone who has watched Clemson's defensive coordinator progress over the years has to agree. Heck, anyone who watched his defense shut down Georgia Tech last week has to agree.

The Tigers dive into this week's showdown with Louisville with Venables' unit once again in the top five nationally in total defense, passing defense and third-down conversion defense. Clemson had the nation's best unit in 2014.

So what's he still doing as an assistant at a prime age (45) in his career?

"I think he'd be a great head coach," Dabo Swinney said. "I know he's had opportunities to be head coach. I just don't think the right opportunity has come along that he's wanted for whatever reason."

After 21 years as an assistant coach at three high-profile programs (Kansas State, Oklahoma, Clemson), there's not much more for Venables to accomplish at his current level.

Overqualified? Absolutely. At 29, his name surfaced at Missouri for the job eventually taken by Gary Pinkel. At 45, he is making a $1.4 million for a team that played for the national championship last season.

Yes, Venables should be a head coach. That doesn't make him any different than a collection of bright, up-and-coming assistants across the country.

Except it does.

Using USA Today's assistant coach database, CBS Sports crunched the numbers. Venables is believed to be among only five current college assistants in his prime age group making more than $1 million who were never head coaches.

The others are LSU defensive coordinator Dave Aranda (40, $1.3 million), Alabama defensive coordinator Jeremy Pruitt (42, $1 million), Florida defensive coordinator Geoff Collins (45, $1 million) and Louisville defensive coordinator Todd Grantham (50, $1.3 million).

The USA Today database reaches from 2009-15, which basically reflects the beginning of the $1 million assistant era. In that time, 14 assistants surpassed the $1 million mark. (The list does not contain private institutions, which are not required to report all salaries.)

Five of those 14 either previously had been or became head coaches. Two -- Monte Kiffin (Tennesse) and Cam Cameron (LSU) -- no longer have college jobs.

Remember the parameters: Young millionaires in the 40-50 age group. The average age of this season's 19 first-year full-time head coaches was 41.6. Eleven of those were previously coordinators with an average age of 38.

It's time, then, for Venables, who has at least 20 years left in a career that began in 1993 as a K-State grad assistant. The list above doesn't include the likes of 59-year-old Texas A&M defensive coordinator John Chavis, who became a millionaire assistant at age 57 in 2013. Nor does it include Virginia Tech's Bud Foster, who surpassed $1 million in 2014 at the age of 57.

They truly do look like lifers at their current positions. Not so with Venables.

"I really believe that my job is better than a majority of head coaching jobs that are out there ...," Venables said during the College Football Playoff. "There are not many places where you can have it all. I believe that I have been at a few places I have had it all, and I don't want to let it go."

I asked around this week about Venables. One FBS head coach said athletic directors these days are more prone to hire offensive assistants.

"Win the press conference," he said. "This is the era of scoring points. If he was a DC in the SEC, he would have a better chance."

Seventeen of the 29 new hires in the offseason had offensive backgrounds. One person who works for a coaching search firm countered, "Concentrating on one side of the ball is a mistake. Leadership is No. 1. That does not come because you come from one side of the ball."

The question still lingers as Brent Venables prepares for one of the biggest games of his career: Why isn't he a head coach?

"I can't answer that," Swinney said.