Jacob Kiplimo gives world record a scare, wins Chicago in 2:02:23 as Conner Mantz (2:04:43) DESTROYS American record

CHICAGO – Half-marathon world record holder Jacob Kiplimo of Uganda showed no fear in marathon #2 today at the Bank of America Chicago Marathon. He gave the 2:00:35 world record a scare before settling for the win in 2:02:23, the second-fastest time ever run in Chicago.

Boosted by a tailwind at the start, Kiplimo and defending champ John Korir of Kenya went out super fast — 13:58 for the first 5k (1:57:51 pace). They hit halfway on world record pace (60:16), and the next few miles were even faster than that pace even though the final pacers dropped out at halfway. At 25k (71:12), the leading duo were on 2:00:10 pace. By 30k (1:25:31; 2:00:16 pace), Kiplimo was all alone.

He was still on world record pace at 22 miles (1:41:05 – 2:00:28 pace at mile 22) but Kiplimo’s pace would slow dramatically to the finish. His final 5 mile splits were 4:46, 4:50, 4:55, 5:05 and 5:20 (WR pace is 4:35.95 per mile), but he still held on for his first marathon win. After crossing the finish line, Kiplimo appeared to be in pain. After collapsing to the ground, he had to be helped to his feet by race director Carey Pinkowski.

Kevin Morris photo

Behind him, as promised, American Conner Mantz went out very aggressively. He hit 5k in 14:23 (2:01:22 pace) and 10k in 29:20 (2:03:46 pace). At halfway (62:18), Mantz was still on pace to break Khalid Khannouchi’s 2:05:38 American record, which had stood since 2002 and, that’s exactly what Mantz did as he ran 2:04:43 to smash the American record and finish 4th overall.

“What took you so long?” joked Khannouchi, who was in the finish area to congratulate Mantz in person.

Tokyo 3rd placer Hawi Feysa of Ethiopia (2024 Frankfurt champ) had a big day as she lowered her pb from 2:17:00 to 2:14:56 to win the women’s race and become the fifth-fastest woman in history. Natosha Rogers was the top American woman, finishing 6th in a 2:23:28 pb (2:23:51 previous pb). *Top 30 Results

Quick Take: Kiplimo showed no fear in marathon #2 and took the next step towards marathon stardom and made history for Uganda in the process

The opening splits in this one were wild. With perfect conditions (54 degrees, sunny, tailwind of 9 mph wind out of the SE at start), the guys got after it. Even though the splits were super fast, Kiplimo looked totally relaxed, which makes sense as he’s run 56:42 in the half-marathon — 48 seconds faster than anyone else.

Around 18 miles, LetsRun.com co-founder Robert Johnson’s 7-year-old son walked into his office and saw Kiplimo all alone and asked him, “Is that guy going slow?” No, he wasn’t, but we understand why a child would ask that as Kiplimo just looks so relaxed.

In the end, a world record was not to be. Here are Kiplimo’s mile-by-mile splits on the way home and his 5k splits.

5km Splits

Given all he has accomplished at 10,000 meters, the half marathon, and cross country, expectations were very high for Jacob Kiplimo when he stepped up to the marathon in 2025.  So far, so good.

Kiplimo debuted with a very solid 2:03:37 in London in April, finishing 2nd behind the planet’s best marathoner in Sabastian Sawe. Today’s run was even better. Kiplimo took almost a minute off his personal best – 2:02:23 ranks him 7th on the all-time list – and moved up a step on the podium to earn his first marathon victory. The win was significant for Kiplimo’s country as it’s the first victory in Chicago for a Ugandan athlete. In fact, it was the first victory by a Ugandan in any World Marathon Major, though Ugandans have won the Olympic (Stephen Kiprotich) and World Championship (Kiprotich, Victor Kiplangat) marathons.

It’s hard to predict the future, but after a second-place finish in London and now a win in Chicago, it’s safe to say Kiplimo is going to have a great marathon career. Remember he’s only 24. Eliud Kipchoge didn’t debut unil he was 28. And that’s not something that can be said about 5,000/10,000 world record holder Joshua Cheptegei (who has finished 37th in Valencia and 9th in Tokyo in two attempts) or many of the most-recent half marathon WR holders. Here is a chart showing you how the most recent half-marathon WR holders have done in the marathon.

And Kiplimo still has room for improvement. Before London, Kiplimo said he usually wouldn’t run more than 100 miles per week during his track career. For Chicago, Kiplimo said he averaged 155 per week for a stretch of training. If he can stay healthy while keeping up that sort of workload, there is no reason why he cannot continue to improve over the next few years.

The world record could be in jeopardy in 2026

Kiplimo dropped Korir at 18 miles, but his winning “move” was not much of a move. The damage had already been done in the preceding miles, and Korir simply could not keep up any more after some aggressive early running. The first 5k, with a 9 mph tailwind at their backs, was covered at 1:57 pace, and Korir made another big push after halfway as he split 14:06 from 20-25k (1:58:59 pace), dropping everyone but Kiplimo. With two men on 2:00:10 pace at 25k, the race was setting up as an epic duel between the two pre-race favorites.

Kiplimo would not pick up the pace – in fact, after that 14:06, he would slow every 5k to the finish – but the 14:19 he split from 25-30k was still 2:00:49 pace, and that was enough to shake free of Korir, who would drop out just after 20 miles.

Kiplimo would really struggle towards the end and struggled to stand on his own at the finish, but he gave Kiptum’s 2:00:35 world record a scare as he was still on WR pace as late as 22 miles (he hit 22 in 1:41:05, which is 2:00:28 pace). 2:00:35 remains a very tough record, but Kiplimo and Sabastian Sawe – whose 2:02:16 in Berlin was worth well under 2:02 in better conditions – are good enough to challenge it in 2026.

Several of those who went with the hot pace really paid for it

When we heard the lead pace group was aiming to hit halfway in 60:30, we thought it only made sense for two guys to go with it: Korir and Kiplimo. No one else was ready to run that fast, and that was correct – and in the end, even Korir couldn’t handle it after they went out even faster than planned at 60:16.

2022 London champ Amos Kipruto held on well enough to finish 2nd in 2:03:54 but three of the five men who went out in 60:16 paid for it. Korir dropped out, Philemon Kiplimo faded to 8th in 2:06:14, and Timothy Kiplagat finished 12th in 2:07:42

Former Hofstra runner Alex Masai breaks out with podium finish

In four years in the NCAA at Hofstra University on Long Island, Kenya’s Alex Masai only qualified for NCAAs on the track once. He ran solid times of 13:24 and 27:45 at nationals, but that was only good enough to place him 10th (5k) and 6th (10k). He was an All-American in cross country, but his best finish at NCAA XC in two appearances was 32nd at the COVID-delayed championships that were held in March 2021. Those championships were won by a guy Masai beat by six seconds today: Conner Mantz.

Masai signed with HOKA NAZ Elite out of college and ran well enough in his first two marathons – 2:08:51 in his debut at Chicago last year, then 2:08:03 in Rotterdam in April. But he reached an entirely new level with his run on Sunday. After going out with the second group and hitting 62:19 at the half, Masai found himself in a battle with Mantz for the final podium spot and won that battle, pulling away late to finish 3rd a massive pb of 2:04:37. Just another reminder of how much talent there is in the NCAAs these days.

Galen Rupp takes a step forward in his comeback

For most of his career, Galen Rupp would not have been happy to finish 16th in a marathon in 2:09:41, beaten by three Americans. But the 39-year-old Rupp is in a different stage of his career now, and if he is being realistic about his current situation, he should view his result today as a positive step. Rupp went out with the third group, hitting 64:07 at the half, and though he slowed down over the second half (65:34), he didn’t totally blow up and held on to finish. This was his best marathon result in two years, since he ran 2:08:48 at 2023 Chicago.

Obviously Rupp will have to run a lot better than this if he is to make it to a fifth Olympic Games in 2028. But Rupp said before the race that he felt his healthiest in years and he showed today he can make it through a full buildup and a marathon in one piece. The next step is tougher – staying healthy and building on what he ran in Chicago. But Rupp showed signs of life today.

Wesley Kiptoo took a big swing in his first race as an American

The US elite field received a boost on Saturday night when it was revealed that Wesley Kiptoo, the 2021 NCAA indoor 5k champ for Iowa State, became a US citizen on September 2 and is now eligible to represent the US after transferring his allegiance from Kenya. Kiptoo, who trains with Alex Masai as part of HOKA NAZ Elite, went with Mantz’s group and hit halfway in 62:20, but started getting dropped shortly after that point.

Kiptoo faded quite a bit over the second half, splitting 66:42 to finish 14th in 2:09:02, but he was still on pace to run 2:05:40 as late as 20 miles. He may not have the ability to run with Mantz just yet in the marathon, but clearly he has the self-belief.

Another guy to note in the 2028 Olympic picture is Zouhair Talbi, who was 11th today in 2:07:27. Talbi, who became a US citizen in January, is not eligible to represent the US yet, but he should be by the time of the ‘28 Trials. He was the second American behind Mantz today and his 2:07:27 would rank 6th on the US all-time list (his pb is 2:06:39 from Houston last year).

Ethiopia’s Hawi Feysa becomes the sixth woman in history to break 2:15 – and half of them are in her training group

The 26-year-old Feysa, who won Frankfurt last year and was 3rd in Tokyo this year, broke out in a big way today, lowering her pb by more than two minutes from 2:17:00 to 2:14:56, running near-even splits of 67:30-67:26 to win her first career major. Last year’s Valencia Marathon champion Megertu Alemu ran a little behind Feysa for most of the second half, and was still within 17 seconds as late as 22 miles, but Alemu would fade over the second half while Feysa would keep it going to the finish.

There have only been seven sub-2:15s in the history of women’s marathoning by six athletes, and five of them have come in Chicago. Three of those sub-2:15s have been been by members of the group coached by top Ethiopian coach Gemedu Dedefo: Feysa, Tigst Assefa, and Amane Beriso.

Kevin Morris photo

The 7 sub-2:15s in women’s marathoning history

1. 2:09:56* Ruth Chepngetich, 2024 Chicago
2. 2:11:53 Tigst Assefa, 2023 Berlin
3. 2:13:44 Sifan Hassan, 2023 Chicago
4. 2:14:04 Brigid Kosgei, 2019 Chicago
5. 2:14:18* Ruth Chepngetich, 2022 Chicago
6. 2:14:56 Hawi Feysa, 2025 Chicago
7. 2:14:58 Amane Beriso, 2022 Valencia

*Currently provisionally suspended for an anti-doping rules violation

One Ethiopian who did not fare as well was Ejgayehu Taye. The 14:12/29:50/64:14 woman was making her debut in Chicago, and though she went out with the leaders in 67:38, she could not hang on and struggled home in 2:51:35.

Natosha Rogers takes top American honors in her third marathon

Rogers, who has been training in Denver with Steve Magness coaching her remotely, felt good about her buildup coming into the race but was concerned about her fueling, which has been a constant struggle for her since moving to the marathon last year. Even after running 2:23:51 in Nagoya in March – a big improvement from her 2:34:51 debut at the Olympic Trials – Rogers was still worried about how her stomach would cooperate today. Thankfully, she experienced no issues, and was able to run a 23-second pb of 2:23:28 to finish as the top American in 6th.

“A lot of it was mind over matter,” Rogers said. “I don’t know if the stars aligned today for me, I didn’t feel sick at all. I’ve been struggling so much with that every single race. Your whole body goes lactic, it’s awful. You’re not reaching your full potential.”

Rogers, who made the 5k and 10k teams for Worlds as recently as 2023, said she does not do a ton of mileage for a marathoner – she maxes out around 85 a week – but supplements that with pool work almost every day, a mix of swimming and aqua jogging.

2024 Olympian Dakotah Popehn, who had come in hoping to run 2:20 or faster, was on track for a big pb after hitting halfway in 70:26 but could not hold it. Today’s 7th-place finish was an improvement on her recent runs in New York (17th) and Boston (16th), and she still managed to improve her pb by running 2:24:21 – just not by quite as much as she had hoped (previous pb of 2:24:40).

Talk about the race on our world-famous messageboard.

• Official 2025 Chicago Marathon Live Discussion Thread
• An American has run 2:04 in the marathon – Mantz gets the American record in Chicago (2:04:43)
• galen rupp 2:09 marathon
• Ed Eyestone: “if we have athletes that are testing positive from certain systems, those managers should also be disqualified”
• Wesley Kiptoo becomes American citizen, will compete as US athlete “immediately.” He’s running Chicago. Could he beat Mantz to AR?

More: Coach Ed Eyestone calls for lifetime bans for doping positives, open to bans for top agents

You can watch a full race replay below.