2024 Olympian Emily Mackay Has Parted Ways with New Balance Boston

Less than a year after qualifying for her first Olympic Games, US middle distance runner Emily Mackay and New Balance Boston have parted ways. The news is surprising as Mackay, 27, is coming off a breakout 2024 season in which she earned the bronze medal in the 1500 meters at the World Indoor Championships in Glasgow and finished 2nd at the US Olympic Trials in 3:55.90, moving her to #3 on the US all-time list behind only Shelby Houlihan (3:54.99) and Nikki Hiltz (3:55.33). Mackay’s agent Ray Flynn confirmed the news to LetsRun.com.

Kevin Morris photo

Mackay ran collegiately at Binghamton University, where her best NCAA finish was 6th in the 1500 meters as a senior in 2022. She joined New Balance Boston that summer. Training under coach Mark Coogan and alongside Olympians Heather MacLean and Elle St. Pierre, Mackay improved rapidly as a professional. After lowering her 1500 pb from 4:08.97 to 3:59.99 in 2023, Mackay was one of America’s best female middle distance runners in 2024. In addition to her 1500m exploits, her 800m season’s best of 1:57.87 ranked sixth in the US last year.

Mackay finished 4th in the 3,000m at the US indoor championships in February 2025 and most recently took 2nd in the 1500 at the Sound Running Track Fest in California on May 24.

Flynn told LetsRun that Mackay remains sponsored by New Balance and said that to his knowledge, she has not yet made a final decision on a new training setup.

New Balance Boston has been without a few of its biggest stars this spring as St. Pierre gave birth to her second child on May 6 and new signing Parker Valby has not raced since February 2 due to injury.

Coogan via text declined to comment for this story; Mackay did not respond to an email from LetsRun.com.

Talk about Mackay’s departure from NB Boston on our world-famous messageboard / fan forum: MB: NB Boston – Is Something Up? Confirmed; Emily Mackay has left group