My opponent, playing defense, called a foul on me, the offensive player for the following situation. For clarification, there was body contact, however I did not call a foul, and considered the contact incidental.
My teammate sent me a somewhat floaty pass directly vertical down the field. I had about 2 steps on my opponent both travelling in the same direction following the disc. Once I had gotten to the point under the disc at which I thought I had best position to jump for the disc, I stopped. Admittedly, this was not directly under the disc; it was the point where I could prevent my opponent from getting to it while also being able to jump for the disk; essentially using my initial 2 step advantage to box out the defender.
The defender was watching the disc and did not see me stop my forward motion. Surprised, he ran into me and called a foul. I claimed I had established position here, stopped and was going to go straight up for the disc. His argument (he was particularly confident that he was in fact very knowledgeable of the rules) was that I had interrupted his running line and this was illegal. Not having a rule book handy I was particularly flabbergasted by his take and therefore not firm in my stance that I was in the right.
However, going back through the rule book, I feel both interpretations could be considered so I want some clarification if this or a similar situation arises.
His argument settles around Blocking Fouls:
XVI.H.3(c)c) Blocking Fouls
(1) When the disc is in the air a player may not move in a manner solely to prevent an opponent from taking an unoccupied path to the disc and any resulting non-incidental contact is a foul on the blocking player which is treated like a receiving foul (2) A player may not take a position that is unavoidable by a moving opponent when time, distance, and line of sight are considered. Non-incidental contact resulting from taking such a position is a foul on the blocking player.
I might argue that that my position was avoidable if the defender was watching me instead of the disc, but he clearly thought I was taking a position where contact was unavoidable. He might also have thought that my stopping prevented his path to the disc.
My counter to this argument might simply be XVII:
XVII.A: Each player is entitled to occupy any position on the field not occupied by an opposing player unless specifically overridden elsewhere, provided that no personal contact is caused in taking such a position.
or, XVI.H.4 (which supercedes any of the other rules, however it wasn't dangerously aggressive behaviour, but he did collide with a stationary opponent)
4. Reckless disregard for the safety of fellow players or other dangerously aggressive behavior (such as significantly colliding into a stationary opponent), regardless of whether or when the disc arrives or when contact occurs is considered dangerous play and is treated as a foul.
I'd be happy with others thoughts on this, because based on his interpretation of the blocking foul rules, I feel like I would have needed to have given up optimal disc-catching space that I felt entitled to, just to get out of the way of his movement. It is also a little unusual because the defender called the foul on the offensive player.