With the Boston Marathon fast approaching, the race’s leading American storyline has taken an unexpected turn. As some runners prepare for the ambitious ‘Double Boston’ challenge and elites chase their fastest times, one American record holder has ended his buildup abruptly after announcing his withdrawal.

In a statement, Conner Mantz, the fastest American marathoner, announced that he is withdrawing from the 2026 Boston Marathon due to fitness concerns.

“Unfortunately, my fitness has not progressed well enough for me to be able to race the upcoming Boston Marathon at my best,” Mantz said in a statement.

“I am very disappointed, but look forward to being back racing soon,” he said.

It will mark the first time since 2022 that the 29-year-old will miss a marathon, as he has run every possible event since then. That includes the 2024 Olympic trials and the 2025 United Airlines NYC Half Marathon, where he set another American record.

The 29-year-old was among the American favorites to podium at the 2026 Boston Marathon, especially after he recently broke a 23-year-old American record in October. Mantz ran the Bank of America Chicago Marathon in 2:04:43 to finish fourth, setting a national record and matching his best-ever finish in an international marathon.

But since then, the American has struggled with a series of injuries and was hoping to rebuild his fitness in time for the Boston Marathon.

In fact, Mantz has been consistently running marathons since he was 12, registering 1:22:43 in his very first half-marathon. Since then, the American has been a staple on the circuit and finished as the top American in his last six marathons, including the 2024 Olympics, where he placed eighth.

It’s why many expected him to be the one to end the USA’s five-year podium drought at a major marathon, but with Conner Mantz out, the focus will now shift to other marathoners.

Canada’s Ben Preisner hoping to impress on his Boston Marathon debut

While America’s fastest marathoner will be out of contention for the Boston Marathon, they’ll have plenty of representatives at the event. Two-time Olympic medalist and the last American man to podium at a major marathon, Galen Rupp, and one-time Olympian Clayton Young will be a part of the elite pack.

Like Mantz, Young is recovering from injury and partnering with Brooks Running to regain full fitness ahead of the Boston Marathon.

And he’s not the only one hoping for a good result, as Canada’s Ben Preisner will make his major marathon debut at the 2026 Boston Marathon. The third-fastest marathoner in Canada’s history, Preisner will run alongside fellow Canadian Rory Linkletter, who placed in the top 10 at the Boston Marathon last year.

However, while Preisner has been a fixture on the Canadian marathon teams, this will be his first marathon major, and he has high hopes.

“I really want to compete with the front pack and be a factor in the race. I think it goes without saying that Boston is probably the most iconic marathon in the world,” Preisner told Canadian Running. “I’ve been running marathons for five years and have never done a marathon major; it’s probably overdue.”

He won’t be the only elite on the field as Kenya’s Benson Kipruto (winner of the TCS New York City Marathon) and 2024 Boston Marathon champion Sisay Lemma will be a part of the pack. And while Team USA will feel Conner Mantz’s absence, it now opens the door for runners like Galen Rupp or Clayton Young to step into the spotlight and make a defining impact.