Farnsworth's left index or forefinger was wrapped in tape, which was protruding from his glove as he went through batting practice shagging balls in center field. The dog's bite reached a tendon, but did not cause serious damage.
"My dogs got in a fight this morning and I just tried to break it up and they bit me in the process," Farnsworth said.
Farnsworth said he owned two American bulldogs, one about 80 pounds and the other about 90 pounds. They're named Strike and Rambo. The incident happened about 7:30 a.m. CT Tuesday morning when the dogs got into a scrap apparently over sharing the affections of Farnsworth's children.
He's not sure which dog bit him this morning at his Leawood, Kan., home.
"I think it was Rambo," said Farnsworth. "I don't know. I reached in there and started grabbing dogs and throwing dogs. And one of them got me. One of those things that happens. It's never pretty. I've had to do it a few times and it's ugly."
The dogs were current on shots so he has no concerns about rabies.
"It hurts a little bit, but no big deal. Just a flesh wound," he said.
Royals manager Trey Hillman said that Farnsworth was not expected to miss any time.
"Not planning on it, planning on wrapping it up and having him available today," Hillman said.
Farnsworth was at least able to grin about the incident.
"That's how I start my mornings off," he said. "Wrestling with bulldogs."
Dick Kaegel is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.