The Chicago Marathon has unveiled its 2025 elite fields, and the men’s side in particular features perhaps the most compelling head-to-head matchup that the race has assembled in years. On the men’s side, the combination of the returning champion, rising stars, and a potential record-setting showdown gives this year’s race the feel of a defining moment in the sport.
The women’s field, meanwhile, is clouded by the absence of Ruth Chepngetich after her provisional doping suspension, yet still offers intrigue through a trio of capable contenders and a pack of hungry Americans.
Beyond the rosters themselves, this year’s Chicago Marathon serves as a stage for larger narratives: the pursuit of records, the generational changing of the guard, and the ongoing super shoe wars that continue to shape the sport.
Here are five key storylines to watch as October approaches.
1. John Korir’s Bid for Greatness
John Korir has already proven himself a champion, winning Chicago last fall and Boston earlier this year. But 2025 could mark his transformation from top-tier marathoner to generational figure. Korir has publicly voiced his belief that he can dip under 2:01 — rarefied territory reached only once before, when the late Kelvin Kiptum shattered the world record in Chicago in 2023. Korir’s ability to negative split, as shown by his blistering 60:25 second half in last year’s Chicago race, suggests he has the tactical range to take bold risks and deliver history.
Should he succeed, it wouldn’t just cement his place in marathon lore; it could signal the arrival of a new era, with Korir stepping into the vacuum left by Kiptum’s tragic passing and Eliud Kipchoge’s twilight years.
2. Jacob Kiplimo’s Marathon Potential
If Korir represents proven excellence, Jacob Kiplimo embodies tantalizing possibility. The Ugandan half marathon world record holder ran a promising 2:03:37 debut in London earlier this year, and many in the sport view him as the likeliest candidate to one day break the two-hour barrier under official conditions. Chicago offers him the chance to test himself against Korir in a head-to-head duel, one that could accelerate his marathon development dramatically.
The pacing strategy in Chicago will be critical. If the rabbits are instructed to hit halfway in under 60 minutes, Kiplimo’s unmatched half-marathon pedigree could give him an edge. If the first half is steadier, Korir’s proven finishing strength might prevail. Either way, the clash between Korir and Kiplimo is the centerpiece of the men’s race — and potentially of the entire marathon calendar.
3. An American Record on the Horizon
For U.S. fans, Conner Mantz is the most compelling storyline. The 27-year-old stunned with a 2:05:08 in Boston — fast enough to beat Khalid Khannouchi’s long-standing American record if Boston’s course were record-eligible. Now, Mantz is openly targeting that mark (2:05:38) in Chicago, where the flat, fast layout favors record attempts.
Mantz has the momentum of a U.S. half-marathon record earlier this year, and his newfound confidence in declaring bold goals suggests he’s ready to seize the mantle of America’s top marathoner. He won’t be alone, either: Galen Rupp returns to Chicago in what feels like a last stand, while CJ Albertson and Canada’s Rory Linkletter add further intrigue. Should Mantz deliver, he could reset American marathoning for the next decade.
4. The Women’s Field Faces a Shadow
The women’s field is, by contrast, defined as much by absence as presence. Ruth Chepngetich’s provisional suspension after a world-record-breaking run in Chicago last year has cast a long shadow. Without her, the top end of the field lacks a marquee name, but that may create space for new stars to emerge.
Magertu Alemu of Ethiopia, a past Chicago podium finisher and Valencia champion, leads the charge, alongside countrywoman Hawi Faysa and Kenya’s Irene Cheptai. Behind them, a quartet of Americans — Lindsay Flanagan, Natosha Rogers, Gabby Rooker, and Olympic finalist Dakota Popahn — could form a competitive pack, each chasing personal breakthroughs. Though the women’s race may not produce record times, it has the makings of a hard-fought and compelling battle.
5. Chicago as the Super Shoe Stage
No current marathon story is complete without a subplot about shoes, and Chicago is Nike’s showcase event. In 2023, Kelvin Kiptum obliterated the world record in an unreleased pair of Alphafly 3s, igniting months of hype. With that shoe now nearly two years old and rivals like ASICS and Adidas pushing the innovation envelope, industry watchers expect Nike to unveil its next-generation “super shoe” on the streets of Chicago this fall.
The most likely candidates to lace them up? Jacob Kiplimo and Conner Mantz, both Nike athletes, who could provide the ultimate marketing payoff by delivering a world record or American record in the brand’s newest prototype. With Korir — an ASICS athlete — threatening to spoil the party, the shoe wars add an extra layer of drama to an already loaded race.
The 2025 Chicago Marathon is shaping up as a study in contrasts: a men’s race bursting with potential records and rivalries, and a women’s race searching for a breakout star in the absence of its reigning champion. Add in the ever-present intrigue of shoe technology, and Chicago promises to once again sit at the center of the global running conversation this fall.
