Long Passes Foul Question?

[bballplayer]

A long pass is made from one baseline. The intended receiver
is covered by an opposing player. The intended receiver is
facing the closer sideline and the pass is made to the
outside. The defender is the inside. The intended receiver
backpedals a step and steps on the opposing players foot. The
opposing player is back pedalling. There is no body contact,
but the intended receiver falls. Is there a foul? I was
playing in a friendly game and am wondering about the rules.
He claims I was underneath him but neither of us was jumping.
He stepped on my foot. He did not land on my foot. Some rule
clarification would be great.

bballplayer