Chris Chase, USA TODAY Sports

The world's oldest marathoner completed his last race on Sunday at age 101, crossing the finish line in the Hong Kong marathon's 10-kilometer race and retiring after 13 years of competitive running.

Fauja Singh took up the sport at age 89 as a way to cope with the deaths of his wife and son. Initially, he took part in the sprints, but was convinced to try longer runs after some encouragement from training partners. When he saw a marathon on television, Singh took up the race.

He ran his first marathon in 2000 and completed eight more, finishing with the 2011 Toronto Marathon. That should have put him in the books as the oldest person to ever complete the 26-mile race, but Guinness didn't acknowledge the record because Singh's passport birthday (April 1, 1911) wasn't considered valid. He needed a government-issued birth certificate, which India did not provide at the time.

Good for Guinness for taking a stand for integrity and not letting sham records into its pages. Just think of how would it look if they let a 101-year-old man enter its hallowed pages without a proper birth certificate. Such a travesty would besmirch all those "largest collection of Hello Kitty memorabilia" and "most toilet seats broken over head" records.

Singh, who lived in India for most of his life but moved to London to be with another son, continued running shorter races until Sunday.

He finished the Hong Kong 10k in 1 hour, 32 minutes (a little less than a 15-minute mile).

"I will remember this day," Singh told reporters minutes after crossing the finish line. "I will miss it."