Had this once a while back in a PONY tournament -
Score 0-0 in like the 4th inning; R1 on 2B, I have the plate. B1 hits the ball to deep short, where F6 stabs the ball deep in the hole, and decides to try and get R1, who is trying for 3B. F6 throws the ball past F5, and the ball goes to the wall of the enclosed field, both F2 and F5 chasing the ball. Meanwhile, R1 is motoring around 3B, trying for home. F1, who has started to go for the ball also, realizes HP is unprotected, and goes to cover......running about 4 feet directly if front of R1 about 3/4 of the way down the 3B line . I, of course, immediately stick my left arm out, as F1 waits directly in front of HP waiting for the ball, gets it and tags R1. I, of course, call R1 out, killed the ball, and then awarded her home.
Now, at the time, I would have had two OBS on F1 in ASA, but since PONY at the time had not yet adopted the ASA rule of needing the ball to block, I still had the other one. And yes, the offensive coach went nuts...but I stopped listening when he started in with the 'there wasn't any contact' business. And also yes, it turned out to be the only run in the game.
Perfect non-contact OBS, as far as I am concerned....