“Johnny Football” Manziel has told TMZ he’s going to be “completely sober” by July 1.

That’s tomorrow.

I want to offer the young man a bit of unsolicited advice.

“Tomorrow” never comes when you place a deadline such as that on yourself.

The one-time Texas A&M University football great and former Heisman Trophy winner has been on a horrendous spiral that has ruined his professional football career.

Worse, it is ruining his life.

I am pulling hard for Manziel to pull his head out of whichever body cavity he has inserted it. I want him to succeed in life. Whether he’s able to regain his athletic form would be an added plus.

However, allow me this one final bit of advice.

I once smoked cigarettes like a freight train. Two-plus packs a day, man. How did I quit the weeds? I wadded them up and tossed them into the garbage.

I quit cold turkey … on the spot. That was more than 36 years ago.

I didn’t wait for “tomorrow.”

One does not put such artificial deadlines on ending bad behavior.

If the young athlete intends to sober up, he’d better just act immediately on his intentions and not wait for the sun to rise the next day.

Too many celebrities have learned in the worst way possible that the sun might not shine.