I don’t get it.

You bomb the easiest part of the biggest job interview of your life.

Not because of a slow 40-yard dash. Not because of a questionably low number of bench press repetitions. Heck, it’s not even because of a terrible performance on the infamous Wonderlic test.

Sources told Fox Sports Tuesday that former Iowa defensive lineman Christian Ballard tested positive for marijuana in the February NFL Combine.

Like every other player invited to the Combine, Ballard had to expect the drug test.

He knew it was coming.

And like Wes Bunting —the National Football Post’s director of college scouting — told me, "Even guys who smoke dope, even they know, just hold off for a couple weeks or months until you get this over this."

That’s not to say Ballard is a "dopehead." During a brief phone interview last week, there was no indication that this was someone willing to possibly jeopardize his career. He sounded like someone who was genuinely excited to get drafted and get playing at the next level. Like someone who was focused on football, not a lifestyle that could cost him money and respect.

Still I don’t think it’s too much to ask to expect better than this from him, or anyone else.

Fortunately for Ballard, he’s a coveted prospect. He’s a 6-4, 283-pounder who runs a 4.7 40-yard dash. With the help of the Iowa coaching staff, he molded himself from a high-school tight end into one of the Big Ten’s top defensive linemen. It will be hard for any team to pass on Ballard’s athleticism and versatility.

He shouldn’t have too much to worry about as far as his draft stock goes; be shocked if he goes anywhere later than at the beginning of Friday’s third round. There’s no question he possesses talent deserving of a late-first to early-second round pick.

That aside, if I’m in charge of an NFL team’s draft decisions, this is making me think twice.

For NFL hopefuls such as Ballard, these are among the most important months of their lives for determining their future. Why not put your best foot forward for every step of that pre-draft process?

Whether it’s a one-time incident or they’re a habitual user, players should to be able to commit to clean up their habits not only to pass a single drug test but to present themselves as someone a franchise wants to commit to. And if there’s a broader substance-abuse issue at hand, help should be sought — not only for professional reasons but more importantly, for the player’s well-being.

A team potentially investing millions of dollars in you is a big commitment. It means at least one person believes in you.

Why give them one less reason to believe?