Let me tell you a story. You might want to pull up a chair as it could be a long one. You might think it has nothing to with the OP, or refereeing at all. That's fine. But if you can spare a few minutes, bare with me.
20+ years ago I was a trainee teacher. It was approximately mid-way through the year, so I was now taking whole classes on my own. Today's tale concerns a Year 10 class - 14/15 year olds - they weren't enemies of the state, but they were no angels either. 30 teenagers have the potential to ruin anyone's day on a whim.
Last lesson of the day (always the hardest) and they were due to have a test. They knew this and had been told to revise. Now (for me) tests are fantastic - 55 minutes of silence to idle away until the bell goes - but as young inexperienced teacher back then, my workload on the day was high.
I got them all lined up outside the classroom, and when all was calm, invited them in. One lad, the class "rogue" - we'll call him Fred, as I can't remember his name - showed me his arm in a sling as he entered the classroom and told me he'd broken his arm and couldn't write. "I'll sort you out in a minute" I said, "just sit down and I'll get back to you." I was too busy getting them in in an orderly fashion to deal with him at that moment. The classroom wasn't big, and by Year 10 the students are getting big, I needed them all in and sat down, even then there was little room to swing the proverbial cat.
All the students were in, check. Next, I began handing out the papers, whilst issuing the standard instructions: "Don't open the paper yet" etc.
At last all the papers were handed out, everyone had a pen and I was able to utter those words "you may begin", I noted the time and wrote it on the blackboard, along with the finish time.
It'd only been five minutes or so since I lined the class up, but with a high workload and little experience, it had been a stressful 5 minutes. At last I could sit down, take a deep breath, relax a little, and take stock. I started to scan the room - lots of heads down and pens scribbling furiously away. And then my eyes settled on Fred. "Sh$t" I thought - I'd forgotten all about him, what was I to do if he couldn't write? My mind spun back up to whirring at one hundred miles an hour.
But at that same moment, I noticed him slip his arm out of his sling, pick up his pen and start writing. His mate caught his eye, gave a wry smile and then returned to his test.
I never had any problems with Fred or that class again.
i would like to say it was down to my classroom management skills and my natural ability as a teacher. But it wasn't. I got lucky.
Fred didn't have a broken arm, it was a ruse on his part. A test for the teacher, he was hoping to cause mischief, create a reaction. But, through my incompetence, that reaction never came and, when Fred realised it wasn't going to be forthcoming, he just got on with the test. No conflict, no drama, no lost face for anyone. Fred's classmates saw that he hadn't got one over me and so my stock went up in their eyes, but Fred wasn't humiliated in anyway either, so no need for him to react to re-assert his status.
I think a similar thing happened to the OP on the pitch - at the time he didn't think it a threat, and just said "lets get on with it" defusing the whole situation, either by accident or design (but probably accident!), probably the best course of action.
Of course - if I'd remembered Fred's broken arm, I'd have had to have done something about it, and it probably wouldn't have ended well for anyone (conflict rarely does.) Similarly if the OP had realised it was meant as a direct threat he would have had to take some action, but what action can you take to cool down someone who wants to heat up?
Just to re-iterate, in my tale, I got lucky and my incompetence saved the day ... sometimes ignorance is bliss!