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I know puppies are meant to play and it's great for socialising. My dog is now 11 months old and his gundog training's coming on well. we sometimes go for a walk with a friend who has a dalmatian dog (18months). She goes to standard dog training classes (obviously not gundog) but her dog's recall is very poor unless I'm there with my dog, so she only lets it off if I'm there. However, from time to time, the dogs' "play" gets very rough as the dalmatian charges towards my dog, knocking him flying and making him roll over again and again. My dog tries to surrender and just lies on his back to avoid aggravation. At what point does puppy play become fighting? How can we calm the other dog down? I'm worried one day he'll hurt my spaniel who's much smaller - not deliberately, but just cause a leg injury by charging into him. If he's put on the lead for a bit, he's always worse once let off, as if he's got pent up energy from the frustration of being on the lead. 80% of the time the walk nicely together, but we just need to stop the sudden fights / games. Is it because they're both entire males? The dalmatian is not food orientated so no food rewards will work. Any ideas would be great! Thanks