According to the Omaha World-Herald, Ebony, a 7-month-old mixed breed who had been found in Lincoln, Neb., is the lucky pup.
The dog "looks a lot Labrador," said Carol Wheeler, one of the directors of the Hearts United for Animals shelter near Auburn, Neb., about 60 miles south of Omaha.
Wheeler said Wednesday that Knight's co-star, Katherine Heigl, and her family help support the no-kill shelter, and that Heigl's father had already given one of the shelter's 200-plus dogs a new home.
Ebony - spayed, bathed and sporting a pink collar - was flown out to L.A. Tuesday and, according to Heigl's mother, "had no accidents on the way."
Nancy Heigl lives in Southern California, Wheeler said, and often exchanges e-mails with Wheeler about the shelter.
Nancy told Wheeler that Knight, the Grey's Anatomy star who turned 34 on March 26, was surprised and thrilled by the gift.
"They all went out to dinner at an outside cafe," Wheeler said, "and Ebony sat right by T.R. all the time."
"I think they've gotten off to a good start," she said.
Up next for the pup? Obedience training - a gift from Nancy Heigl!