> you have put my mind at rest but when the dogs had a fight it was the shnauzer that came of worst as neither would back down.
What did the fight look like & how did the Shnauzer come of worse? Was there lots of noise, lots of teeth, face-to-face with maybe cheek-biting/neck-biting, but no blood shed? Did the Snauzer walk away or did you 'break it up' ?
When I still had my other dog, pup was a night-mare for stopping play when the oldie told him too, often the oldie would end up sounding like he was going to kill pup (pup thought it was a very good game, playing all rough like that), it would look & sound awful but htere was never any blood-shed, generally oldie would walk off, ignoring pup & if pup was stupid enough to go back for more (which he usualy was) oldie wouldn't bother with all the 'fight' display, he would give a bark, the bark always seemed to let pup know that the game was over. But it wasn't until I left them to it (I would break up the heavy play & step in when pup was OTT) that the oldie learned he could use his bark to make pup behave.
ETA, pup was MUCH bigger than 'oldie', I think this is part of the reason pup didn't bother when oldie physically told him off - it just seemed like a game to him, but if the adult dog was the same breed as the pup, the size difference may have given more impact to the physical warning that play was over.