Mai Baum Returns to Rebecca Farm for His Farewell
As the equestrian world looks to Rebecca Farm for the next leg of the US Equestrian Open, all eyes will be on a 19-year-old gelding whose name has become synonymous with American eventing excellence.
Mai Baum, known to his connections as ‘Lexus’ will compete in his final upper-level competition this weekend at Rebecca Farm—the very same class he won 10 years ago at this Montana venue, marking what was only his second four-star with rider Tamie Smith and their first four-star victory together.
The poetic symmetry of Mai Baum's farewell couldn't be more perfect. A decade ago, he launched what would become a legendary partnership with Smith by winning the Rebecca Farm CCI4*-S. Now, after one of the most impressive US eventing careers, he returns to the same competition, for his final farewell.
Listen to the 'Mai Baum Special' on US Equestrian Open Podcast now.
A Career Defined by Excellence
The numbers alone tell an extraordinary story. With 33 international starts, 20 podium finishes, and 13 wins, Mai Baum achieved a peak EquiRatings Elo of 833—the highest of any U.S. event horse in the past 15 years and ranking among the top 15 worldwide over that span.
The horse's international career began in 2013 with Alexandra Ahearn. The next year at only his second international event, he had his first win in the CCI2*-S at Galway Downs. That victory marked the beginning of what would become a special relationship with the California venue—Tamie returned with him four times, in which they took the win every time.
For all of Mai Baum’s accolades and podium finishes, his story was never written with medals in mind. 
Dressage Mastery
Perhaps no statistic better illustrates Mai Baum's consistency than his dressage record with Smith. Across 29 internationals together, they never scored in the 30s. Their best test came at Tryon in 2021 with a score of 20.4, while their worst was still a respectable 29.9 at Arville in 2021.
Five-Star Prowess
Mai Baum's five-star record reads like a masterclass in big-competition performance. Across five attempts at the level (Kentucky 2021, Badminton 2022, Pratoni 2022 World Games, Kentucky 2023, Maryland 2024), he finished in the top 10 four times. Only a mid-course retirement at Maryland 2024 disrupted their otherwise perfect record, with Tamie choosing to pull up when Mai Baum showed signs of fatigue.
The pinnacle came at Kentucky 2023, where Mai Baum and Tamie Smith became the first American pair to win since Phillip Dutton in 2008. Pre-competition, EquiRatings had highlighted them as the ones to beat, giving them a 66% win chance and an 88% shot at the podium. Despite this, it was still no easy feat. Sitting in third after dressage (24.2), they delivered a textbook cross-country round where they made the time — a decisive move that secured their 3.6-penalty victory.
The Final Chapter
Rebecca Farm is a fitting stage for Mai Baum’s farewell — the site where his brilliance at the highest-level first truly emerged. In 2015, it was here, in the mountains of Montana, that Mai Baum won the CCI4*-S on just his second start at the level.
According to the EquiRatings Prediction Centre, they arrive this weekend with a 61% win chance and an 85% podium chance, practically identical to their Kentucky odds in 2023.
A Legacy Beyond Statistics
While Mai Baum's achievements speak for themselves but his impact extends far beyond ribbons and rankings.
This weekend at Rebecca Farm, the eventing community will witness the end of an era. Mai Baum may be stepping down from the upper levels, but his legacy will endure for many years to come. That it happens where his greatest chapter began makes this farewell all the more fitting.
Listen to The US Equestrian Open Podcast Now
Tamie Smith, Alexandra Ahearn, Ellen Ahearn, and Eric Markell relive the moments that made Lexus unforgettable: from a German auction to Kentucky glory, from heartbreak to heroics.
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