With Minnesota Vikings coach Mike Zimmer gearing up for his 5th surgery on his right eye ... Fetty Wap is offering the guy some ocular advice about how to get through life with one less peeper.
Of course, Fetty ain't shy about only having one eyeball -- he lost the other to congenital glaucoma as a young boy -- and with a detached retina threatening Zimmer's right eye, Wap wants to help out.
"Tell him to come holla at me. I'll show him how to get right with one eye!"
By the way, Fetty says his eye issues haven't held him back at all -- telling TMZ Sports he can still play football ... as long as he's on the left side of the field!