Boston Marathon

Dog Known for ‘Boston Strong' Sign at Marathon Dies After Cancer Battle

Spencer became well-known for his iconic "Boston Strong" sign at the Boston Marathon

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A beloved dog who became a mascot of the Boston Marathon has died after a battle with cancer.

Spencer was known for his iconic "Boston Strong" sign at the race. His owners say he died Friday.



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A portrait of Spencer was unveiled early last month at marathon headquarters at Fairmont Copley Plaza. He also received a marathon medal.

Spencer, a dog who became famous for his presence at the Boston Marathon, has been diagnosed with an untreatable form of cancer.

Spencer has long been a friendly face at the marathon, cheering on runners as they pass him on the course.

"I can't tell you how many runners say Spencer was the reason they ran the marathon," his owner, Rich Powers, told NBC10 Boston Tuesday.

Last year, the Boston Athletic Association named Spencer the official dog of the 126th Boston Marathon.

"We at the B.A.A. are saddened to learn of the passing of one of our dearest and most loyal Boston Marathon supporters, Spencer," the organization said in a statement Tuesday. "Spencer annually encouraged participants in Ashland, embodying the unwavering spirit of Boston's athletes as he showed up year after year regardless of the weather conditions. We were honored to have recognized Spencer as the Official Dog of the Boston Marathon in 2022, and extend our condolences to the Powers family, sister Penny, and his many friends and admirers around the world."

"It's heartbreaking to know that he won't be there this year. But in spirit, he'll be there," Powers said. "He had overcome some amazing challenges — he almost died in 2020 from a massive tumor, and then he was able to make the marathon again, which was a miracle. And he's living proof that you can overcome what you thought you couldn't."

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