Therapy dog cheers on Boston Marathon runners with 'Boston Strong' flags

Hundreds of thousands of spectators gathered along a 26.2-mile course throughout the greater Boston area on Monday to cheer on athletes as they ran the historic Boston Marathon — including one very good fan.

Spencer the therapy dog was out in full force during the race, sporting a yellow raincoat, a Red Sox bandana and two "Boston Strong" flags, with his owner, Rich Powers. The pair, from Holliston, Mass., had one mission in mind: to help brighten up the grueling physical challenge with a little bit of cuteness.

CBS News reports that the pair was stationed between mile 2.5 and mile 4 of the race throughout the day, greeting runners and passersby.

Spencer the dog went viral in 2018 when, during another rainy Boston Marathon day, he donned his tiny raincoat and "Boston Strong" flags and posed near the course — the year-old footage of the soggy pup racked up nearly 3 million views.

Powers told Inside Edition at the time that Spencer was a huge hit with athletes and spectators alike.

"We were there to motivate and judging by the faces we saw running, it was a success," he said.

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