M18-20 at Napa Valley Half Marathon: Walton dominates as a field of seven battles the valley

• David Walton won the M18-20 field in 1:14:00 (5:39/mi), finishing 23rd among men overall — a dominant margin of more than seven minutes over second place.
• Mateo Coulson ran the strongest closing leg in the group, posting the 46th-fastest men's split on the 6.9M–Finish segment to secure second in 1:21:16 (6:12/mi).
• Aidan Simonian mirrored that late surge, recording the 164th-fastest men's split on 6.9M–Finish to move up 45 places among men in the back half, finishing third in 1:39:57.
• The M18-20 field spanned nearly two hours from first to last — Walton's 5:39/mi to Tylen Carrasco's 14:37/mi — a testament to the wide range of talent on the start line.

David Walton made the M18-20 race his own from the gun. The 20-year-old from Corona Del Mar moved from 26th to 23rd among men across the first two checkpoints, and his 24th-fastest men's split on the 3.1M–6.9M segment showed he was running with the sharpest mid-race pack in the field. He crossed in 1:14:00, a margin that was never in question.

Behind him, the most compelling story was the back-half charge by Mateo Coulson and Aidan Simonian. Coulson, the 19-year-old from Los Gatos, climbed from 84th to 59th among men in the second half of the race — a genuine move through the field — to finish second in 1:21:16. Simonian similarly found another gear after 6.9 miles, gaining 45 places among men on the closing segment to take third in 1:39:57. Both runners were fading through the middle miles and came alive late; the 18-minute gap between them at the line reflects how much ground each had to make up from different starting positions.

Carlos Ramirez (1:49:39, 4th) held steady early but slipped from 282nd to 357th among men in the final stretch, suggesting the 47°F chill and 12 mph headwind took a toll in the closing miles. Matteo Chiste (5th, 2:09:21) and Hugo Sanchez (6th, 2:28:33) rounded out the field before Tylen Carrasco of Napa completed his race in 3:11:37 — a finish that took real commitment across 13.1 miles.