Under-19 Half: De La Jara-Smith leads the young guns home

• Mariel De La Jara-Smith, 1st in the U-19 field — finished in 2:00:44 (9:13/mi), posting the fastest women's split on the 8M–9.6M stretch.
• Ara Warren, 2nd in the U-19 field — crossed in 2:19:53 (10:40/mi), logging the 5th-fastest women's split on the 4M–6M segment.
• 19:09 separated the two finishers — a gap that tells the story of two very different races unfolding across the same 13.1 miles.

San Francisco's half marathon is no easy proving ground — 59°F with a 14 mph wind and 78% humidity — and Mariel De La Jara-Smith handled it with composure. The 19-year-old from SF held 2nd among women through the first half of the race before settling into 3rd by the midpoint and holding that position all the way home, finishing in 2:00:44. Her sharpest moment came between miles 8 and 9.6, where she put up the fastest women's split of anyone in the field on that stretch — a genuine surge when the race was getting hard.

Ara Warren, 18, from Vacaville showed her own early pop, turning in the 5th-fastest women's split on the 4M–6M segment and sitting 5th among women through the race's first half. The back half proved tougher — she slipped from 6th to 9th among women between miles 8 and the finish — but she crossed in 2:19:53 at a 10:40/mi clip to claim 2nd in the U-19 field and complete her 13.1 miles.

Two finishers, two distinct race shapes: De La Jara-Smith building through the miles and finding her best gear late, Warren front-loading her effort and grinding it out to the line. At 19 and 18 respectively, both have plenty of San Francisco Marathons ahead of them.