Amber Rose & James Harden -- Entering The Friend Zone ... Let's Not Get Serious

Amber Rose and James Harden have decided to put their bangship on hold ... mutually deciding to enter the desolate and barren void known as the FRIEND ZONE ... TMZ Sports has learned.

James and Amber had been rumored to be seeing each other ... with Amber attending a Rockets game in Houston and reportedly gushing to friends about how sweet Harden was.

Rose even publicly proclaimed on "The Breakfast Club" that she might let the NBA's leading scorer sink a bucket on Valentine's day, if he "acted right."

But we've learned the two are officially DUNZO romantically ... and that it was the the distance between them that turned their Sonny & Cher into a Murtaugh and Riggs.

Bottom line -- start lining up fellas ... seems like this is back on the market.