SF Marathon 10K — F80+: Acosta Edges Sammon in an All-San Francisco Showdown

• Mercedes Acosta won the F80+ race in 1:41:54 at a 16:24/mi pace, holding off her fellow San Franciscan by 26 seconds.
• Phyllis Sammon finished 2nd in 1:42:20 (16:28/mi) — separated from Acosta by just 26 seconds across 6.2 miles.
• The final stretch told the story: Acosta posted the 2,277th-fastest women's split on the 4.62M-to-Finish segment; Sammon was right behind with the 2,250th-fastest — meaning Sammon actually ran that closing stretch faster, but couldn't quite close the gap Acosta had built earlier.

Two 80-year-olds, both from San Francisco, both toeing the line at the SF Marathon 10K on a cool, overcast July morning — and they made it a race worth watching. Mercedes Acosta crossed the finish line in 1:41:54, claiming the F80+ title and holding a 26-second cushion over Phyllis Sammon, who finished in 1:42:20.

The late-race split adds an interesting wrinkle. On the final 4.62-mile-to-finish segment, Sammon ran the faster leg — her 2,250th-fastest women's split besting Acosta's 2,277th — but the margin she clawed back wasn't enough. Acosta had built her lead in the earlier miles and managed it well enough to see the finish line first at 16:24/mi to Sammon's 16:28/mi.

At 80 years old, finishing a 10K in San Francisco's hilly terrain — even on a mild, nearly windless morning — is a genuine athletic achievement. That both women did it, separated by less than half a minute, makes this one of the more quietly compelling stories of the day.