A tennis ball flies through the air, followed closely behind by two streaks of white fur.

Gravel sprays from beneath their dogs' paws as they race each other across the fenced-in play area.

A first glance might lead one to believe that the pups share a bloodline, but a closer look reveals distinct differences between the two.

There's Orion, a Siberian Husky who struts a sleek build and has silvery-blue eyes and a majestic, curled tail.

Atlas, meanwhile, has dark brown eyes, the tell-tail (pun intended) backend of a German Shepherd and large ears that stand at attention.

Vikings defensive end Stephen Weatherly got both as puppies in Nashville, Tennessee, and chose their names based on his love for Greek mythology.

"Orion was first. I really liked the name; I used it in a project that I had in college for a line of mineral water," Weatherly explained with a chuckle. "And then Atlas, same thing, Greek mythology."

At the time of this interview, Weatherly had his eye on a white cat at a nearby shelter. Although it didn't end up working out to adopt the feline, he already had a name picked out: Adonis. For the "trifecta," he explained.

Maybe someday.

Weatherly points out that while their variances in appearance may be subtle, the contrast in personalities is much starker.

Orion loves to be the center of attention and shows off a craftier demeanor, according to his owner.

"He's very mischievous, and he does things on purpose. He knows how to open doors," Weatherly said. "He doesn't get into anything unless he feels like he's being disrespected. He's very much that kind of guy."

Weatherly first noticed Orion's "evil-genius side" early on when he realized the puppy was feigning an injury.

"He would fake limps on walks so he wouldn't have to walk anymore," Weatherly laughed. "I thought I had hurt him because he was like 12 weeks and wouldn't walk and started limping, and I'm like, 'Oh my [gosh], I've over-walked him. This is a problem.'

"So I pick him up, I run inside … and poured some food into his bowl, hoping he would feel a little bit better, and he sprinted over to the bowl like everything was fine," Weatherly continued. "So that was his M.O. Also when he was younger, if you ever [scolded] him and flicked your finger at him, not hitting him, but just flick your finger at him, he would immediately start wincing, like winking one eye like you blinded him, so that was also his way to get pity."

And as for Atlas?

The younger dog is called "a big dummy" by Weatherly.

"But I love him for it," the defensive end said. "He's training to be a lap dog; he doesn't understand personal space at all. He'll crawl on the bed, he begs, drops his ears. He tries to get as small as possible, which is hilarious because he's 85 pounds.

"But yeah, this is the evil genius right here, Orion, and Atlas is [his sidekick]," Weatherly added. "Do you remember Pinky and the Brain? Yeah, that's Pinky, and this is the Brain."

Both have learned various tricks – they will sit, lie down, shake and stand on their back legs on command – but only Orion takes after his "dad" in the athletic category.

"Atlas can't catch unless you throw it directly at him," Weatherly quipped, patting the German Shepherd on the head. "And then still it's, like, 50-50."

Continuing to compare the pair of pups, he pointed out that Orion is independent and "only loves me because he knows I control the food." He explained that while Orion tends to toe the line and require more discipline, Atlas is truly a man's best friend.

"German Shepherds, just love them unconditionally, and then they'll love you back," Weatherly said. "Atlas is a big, loveable protector."

He recalled an experience in which he and his then-roommate, Vikings running back Ameer Abdullah, were rough-housing.

"Ameer and I were wrestling, and Atlas thought his father was being beat – which I was," Weatherly admitted. "And Atlas jumped in and kind of nibbled on Ameer."

Whoa, whoa, whoa. Interference.

"Nibbled? Nibbled?" Abdullah interjected good-naturedly.

"He gave him a love nip right behind his shoulder," Weatherly countered.

"I'm probably going to get an infection, I don't know," Abdullah said. "And they shed, as you can see."

He laughed and then added, "No, I love these dogs. They're great dogs."

Weatherly concurs.

Although he's an animal lover in general – he's been known to babysit turtles, Gnevieve and Gretchen, and enjoys his roommate's bunny, Benny – he will always be the biggest fan of dogs.

"I had a dog growing up, and being an only child, I feel like that was like my brother in some regards," Weatherly explained. "I've always just loved them. They're always there. [Whether] I had a great day at practice or a horrible day at practice, they don't know which one is which. They just love me the same.

"I always tell people that dogs are the only creatures capable of unconditional love," he added.