Glen "Big Baby" Davis posted a farewell message to his fans on Tuesday just before he was thrown behind prison bars ... and the former NBA star was surprisingly in good spirits despite what's in store for him.
Check out footage that Davis posted to his Instagram page while he said he was on his way to FPC Duluth in Minnesota ... he had a big smile on his face -- even though he's now about serve the 40-month prison sentence he was hit with earlier this year for his role in a scheme that defrauded the NBA's Players' Health and Benefit Welfare Plan.
Davis held up a peace sign in the vid and told his followers he'll see them around.
"Love you all," he added. "Love y'all. Y'all be good!"
Davis then shut off the camera.
It's, of course, not the first time we've seen Davis holding up well in spite of his impending time in the slammer ... back in July, he actually cracked a few jokes to TMZ Sports about how he thinks his prison sentence will go down.
He stated he'd work on his dream bod, "learn things" and "meet new people."
He also said he anticipated chatting about hoops with fellow inmates -- and given the Celtics' season tips off later Tuesday, it seems there will be plenty to talk about starting Day 1.