These are big, strong, proud 15 year old lads. They have now properly embraced the physical side of the game, I have no issue with that. But when emotions are running high and tackles are late, then a quiet word from a good referee can calm things down. This ref didn't spot what was happening, so I said: "You need to get a grip here ref, or someone's going to get hurt." He didn't like it, but it needed saying.
Thankfully both the managers had words with the lads on both sides who were at risk of losing it. All was well in the end. I totally back the FA Respect campaign and abhor parents who swear and rant at referees. But respect also has to be earned and players have to be protected, sometimes from each other, even if it was a friendly.