Non-mortal combat

Interesting weekend in WV. Our friends, Jessica and Glenn, along with their two young children, came for an overnight visit. They brought their eight-month old yellow lab, Dolly, a sweet-natured pup who likes to jump on people, countersurf and get into the garbage. (Jessica and Glenn are hoping she'll outgrow these habits).
As soon as she arrived, Zorro went into his badass mode, jumping on her, smacking her with his paw, and basically bossing her around. But after we put both of them on the porch, Dolly decided that being herded was a great game. They spent hours running around the porch, occasionally colliding. There was a lot of growling and snapping, and at times it was hard to tell whether they were fighting or playing. But no blood was shed, and at various intervals they would retire to their corners to rest. When we took them on a walk, Zorro pretty much ignored Dolly, even though he was on a leash and she was not (she has good recall: even though she would run ahead, she always looked around immediately when her name was called. We can't count on that with Zorro).
Jessica reports that Dolly, normally rambunctous in the car, slept all the way home. Zorro is pretty wiped out, too. I told him to save his strength because more dog guests are coming: Thanksgiving is less than two weeks away.