Former LA Lakers coach Phil Jackson has finally popped the question to his longtime girlfriend Jeanie Buss — after 12 years of dating — but the real question … could this affect the Zen Master’s possible coaching gig with the Brooklyn Nets?

Our Lakers source tells us the engagement went down on Christmas day, but Jeanie — daughter of Lakers owner Jerry Buss — didn’t reveal the ring until moments ago.

РReported by TMZ.com