Donovan McNabb -- Close Friends Worried About Him ... 'DUI Was No Surprise'

Donovan McNabb's close friends are concerned that his drinking is out of control -- and tell TMZ Sports they've been urging him to change his lifestyle before it's too late.

We spoke with multiple people close to the ex-NFL quarterback who all said the same thing -- they weren't surprised by McNabb's 2nd DUI arrest ... because they all felt it was just a matter of time.

"The thing about Donovan is that he really don't give a sh*t," one friend tells us ... "but he really needs help."

His friends say they've tried to convince him to at least get a personal driver ... but he won't listen. Ditto for Uber.

"He refuses to take Uber for some reason. We have tried to convince him, but he refuses."

His friends say they care about him and want him to get better -- and hope the arrest can finally be the wake-up call he needs.