SF Marathon 5K — NB25-29: Chang Takes the Win in the Bay

• Jiwon Chang (Sunnyvale, CA) won the NB25-29 field in 33:45 (10:52/mi avg).
• Jr Derenoncourt (Oakland, CA) finished 2nd in 55:34 (17:53/mi avg).
• The two-finisher field saw a gap of 21:49 between 1st and 2nd.

The NB25-29 field at the 2025 San Francisco Marathon 5K was a compact two-person race, run under cool, damp conditions — 56°F, 95% humidity, and a 14 mph wind off the Bay. Jiwon Chang, 25, of Sunnyvale made no mistake, crossing the line in 33:45 at a 10:52/mi clip to claim the win outright.

Jr Derenoncourt, 26, of Oakland completed the NB25-29 field in 55:34 — a 17:53/mi average that reflects a markedly different effort on the day. The 21:49 gap between the two finishers tells the story of a race where Chang was in a class of his own within this field from start to finish.

Small fields can still be hard-fought, and both athletes earned their finish lines on a challenging San Francisco course in blustery, humid July conditions. Chang walks away as the clear NB25-29 champion of the 2025 edition.