San Francisco Ultramarathon 2023: Masefield Leads the Men Wire to Wire

• Luke Masefield won the men's race in 6:30:15 (7:27/mi), holding the lead from start to finish across all 52.4 miles.
• Carson Clowes moved from 3rd to 2nd on the back half, finishing 6:37:19 — 7 minutes and 4 seconds behind; John Jones slipped from 2nd to 3rd, crossing in 6:41:44.
• The gap from 4th to 5th was enormous: Pedro Paulino Pais Abreu (7:11:47) and Justin Slingerland (7:41:08) were separated by nearly 30 minutes, with both moving up from their mid-race positions.
• Rodney Martin, 53, reached 13th in 8:27:25 — the oldest named finisher and still running 9:41/mi across a double marathon through the hills of San Francisco.

Luke Masefield never relinquished the top spot. The 30-year-old San Francisco local ran all 52.4 miles of this rare urban ultra — twice over the Golden Gate Bridge, through Golden Gate Park, along the Embarcadero — at a 7:27/mi clip, posting the fastest men's split on the second-marathon leg as well. His 6:30:15 was the kind of performance that makes the lead look comfortable, even when covering back-to-back marathon distances on city streets.

Behind him, the podium reshuffled on the back half. John Jones of New York had held 2nd through the first marathon, but Carson Clowes — running out of Paso Robles — turned in the second-fastest men's split on that closing leg and moved past him. Jones settled for 3rd in 6:41:44 (7:40/mi), while Clowes finished 2nd in 6:37:19 (7:35/mi). It was a catch-up story: Clowes ran the final leg faster, Jones faded just enough, and 4:25 separated them at the line.

Further back, Pedro Paulino Pais Abreu and Justin Slingerland both climbed the standings in the second half — Abreu from 5th to 4th (7:11:47), Slingerland from 8th to 5th (7:41:08) — but the real story was the field spreading out dramatically. The 20 named men span from Masefield's 6:30:15 to Camden Schwiebert's 9:28:35, nearly three hours of racing separating the front of the pack from the 20th finisher, with 41 more men completing the course behind him across a 61-man field.