Ruff. That’s how Saturday started off for Charles Fisher and best friend Bear.

Fisher, with his 7-year-old Labradoodle in tow, had strolled over to Bagel Bob’s near Union Square so he could grab a bite for breakfast. He left the pooch tied up outside while he popped inside the shop on University Place.

But when Fisher, 50, walked out only a few minutes later — grub in hand — Bear was nowhere to be found.

Not only did he lose his appetite, he felt sick to his stomach.

“I walk out the front of bagel shop with my order, and my dog is gone!” Fisher told The Post. “I look left and right, no sign of anybody, no sign of my dog. And so I just guessed a direction.”

A frantic Fisher walked over to 10th Street, where he spotted a man “casually” walking with Bear.

“I dropped my bagels and my coffee, and I started running,” Fisher said. “I caught up to him, and then I started shouting at him like, you know, ‘That’s my f–king dog, what are you doing?’ … and he just looks at me and keeps walking.”

The man, identified by police as 36-year-old Tyrone McQueen, finally dropped Bear’s leash — and Fisher managed to scoop up Bear, who he bought as a pup for more than a grand.

But Fisher wasn’t done yet. He quickly called 911 and kept up his pursuit.

“He never spoke to me. He never responded when I confronted him,” Fisher said of McQueen. “A couple times he broke into a jog. And a couple times he looked back at me … but he never said a word.”

Cops took the alleged dognapper into custody shortly after the chase; McQueen, who has a rap sheet dating back to 2003, including arrests for theft, was charged with criminal possession of stolen property and petty larceny, police said.

Fisher admits the wild morning will make him think twice about leaving Bear unattended.

“She’s of no use as a guard dog,” he joked of his — man’s — best friend.