It's unclear if Bieber intends to fall on his face or not. But the end result is that his he dives into the ground, adjusts his head to get on the end of a cross, and scores a silly headed goal.
Our guess is that he tripped, because only a mad man would decide against tapping it in with his foot in this situation.
It was first spotted on r/soccer and posted on Deadspin.
That's one way to do it.