Conner Mantz, the American marathon record holder, has withdrawn from the 130th Boston Marathon on April 20, citing a sacral stress fracture that has disrupted his training since the autumn. The 27-year-old Utah native — who set the American marathon record of 2:04:43 at the Chicago Marathon in October 2025, breaking a 23-year-old mark — had been one of the most anticipated entrants in this year's elite field.
The injury timeline reveals how quickly elite marathon preparation can unravel. Mantz sustained the sacral stress fracture in the aftermath of Chicago and was unable to run until late January. His training appeared to return to normal through early March before suddenly falling off after March 11, suggesting a setback that ultimately proved insurmountable with just weeks until race day.
In his withdrawal statement, Mantz was characteristically measured: "Unfortunately, my fitness has not progressed well enough for me to be able to race the upcoming Boston Marathon at my best." The decision removes the top American hope from the men's race, where Mantz finished fourth last year — the highest American placing in Boston since 2019.
Mantz's absence is a significant blow to both the race and American marathon running. His 2025 campaign had been historic — American records in both the half marathon (59:17) and the full marathon within a single year. The silver lining is that sacral stress fractures, while serious, typically heal completely with appropriate rest. If Mantz can return to full fitness by autumn, the Chicago or New York City Marathon could offer his next shot at the world stage. For Boston, the American spotlight now shifts to Emily Sisson, the women's American record holder making her Boston debut, and Fiona O'Keeffe, the 2024 Olympic Trials champion.