This former BYU star will miss the Boston Marathon — but other former Cougars will run

Conner Mantz, the Olympic marathoner from BYU and Smithfield, Utah, has managed an uninterrupted streak of eight marathons that stretches back to 2022 in which he produced seven top-seven finishes and an American record.

This is almost unheard of in a sport so fraught with injuries and setbacks resulting from 125-mile training weeks and the perilous 26.2-mile race itself, but that streak is finally coming to an end.

Mantz was scheduled to race in Monday’s Boston Marathon but withdrew three weeks ago due to an injury — a sacral stress fracture.

“It’s tough when you’re the American record-holder and (the Boston Marathon) is wanting you and incentivizing you to run,” says Mantz’s long-time coach, Ed Eyestone. “It’s tempting even when training isn’t perfect, but we made the right call (to withdraw).

“We didn’t want to go there at 80 percent. We need to protect the Mantz brand. We need to respect the event and the marathon and the distance and the competition. This is not the local fun run.”

After claiming two individual NCAA cross country championships, Mantz left BYU in 2021 and undertook professional road racing and marathoning. With the exception of the 2023 Boston race, he has been the top American finisher in seven of those eight races and ran 2:09:00 or faster each time. He seemed to get stronger every year.

In 2025, he set four American records on the road — 20 kilometers (twice), half-marathon, marathon; claimed three consecutive victories in major road races, including the U.S. 20K championships; and placed fourth in two of the world’s most prestigious marathons — Boston and Chicago.

In the latter, he broke a 22-year-old American record by almost a minute, clocking a time of 2:04:43.

“I don’t know if there’s been a better year for an American for a long time,” Eyestone said at the end of the year.

He will be conspicuously absent in Boston.

Mantz’s training partner, Clayton Young, another former BYU NCAA champion and Olympian, will compete in Boston, as planned, but he too has had what Eyestone calls a few “hiccups” in his training build.

Since placing ninth in September’s world championships, Young has struggled to stay healthy. He was scheduled to run the Valencia (Spain) Marathon in December but was forced to withdraw with an injury.

“Clayton is going into this one not having had a perfect build either,” says Eyestone. “We had to shut him down in December. Usually we have a 16-week (training) build to a marathon; we’re going to see how it goes with a 10-week build.”

Another former BYU athlete, Rory Linkletter, will race in Boston on Monday. Like his former BYU teammates, Mantz and Young, Linkletter has been on a hot streak. He set the Canadian record for the half-marathon two months ago in Houston with a time of 59:49 and represented Canada in the world championships and Olympic Games.

He was sixth in last year’s Boston race (2:07:02) and ninth in last fall’s Chicago Marathon (2:06:49)

“He’s had a very good build,” says Eyestone. “I think he’ll run well.”

Kodi Kleven, a former BYU and Utah Valley University runner, will also compete in Boston. She is a three-time St. George Marathon champion and course record holder (2:28:41).

As for Mantz, Eyestone said they still must decide on where and when he will race next.

“He’s going to be fine,” says the coach. “He’ll be back. He’s got a lot of good years left. At the end of the day, it’s not the worst thing to miss a race after eight successful marathons in a row.

“One of the most difficult parts of this sport is having highly motivated and talented athletes who want to do more and more. It might be a good thing to take a break from another race.”