Kipruto's time of 2:01:09 was a new personal best and vindication for the 34-year-old, who had finished second in Chicago last year and third the previous edition.
Amos Kipruto of Kenya dominated a world-class field to finally win his first Chicago Marathon while Ethiopia's Hawi Feysa defended her women's title on Sunday.
Kipruto's time of 2:01:09 was a new personal best and vindication for the 34-year-old, who had finished second in Chicago last year and third the previous edition.
This time, Kipruto pulled clear of defending champion and pre-race favourite Jacob Kiplimo at mile 21 and never looked back.
"Today's race was really good for me... I came here 2024, I became position three; in 2025 I became position two. And now 2026 it was either win or die for me," said Kipruto.
He finished the 48th Chicago Marathon nearly two minutes clear in ideal sunny but cool conditions, briefly sinking to the floor after he crossed the finish line, before quickly rising with a giant grin.
Kipruto, the 2022 London champion, had set his previous personal best finishing fourth at this year's historic London race, where the mythical two-hour barrier was broken.
But he had the spotlight to himself in Chicago.
"The preparation for me toward the Chicago Marathon 2026 was perfect for me. I improved a lot in training for the previous London Marathon," said Kipruto.
"But I said 'let's go (for) Chicago' and let be what will be. Everything is all about a mindset. It was a tough field, but I set my mind, and I said 'let's go.'"
His time makes him the joint-fifth-fastest marathon runner of all time.
Uganda's Kiplimo ultimately slipped back to fourth place.
Tadese Takele Bikila of Ethiopia -- the defending Tokyo champion, making his US marathon debut -- took second, while compatriot Milkesa Mengesha came third.
On the women's side, defending champion Feysa also set a new personal best with a blistering 2:13:33.
"I'm elated to have won the second time," said Feysa, via an interpreter.
She was followed by Sharon Lokedi of Kenya, this year's Boston winner, who stayed with Feysa most of the race but finished 34 seconds back.
"It certainly became quite a battle, especially after the pacemaker dropped out around 33k. But around 35k, that's when I became pretty sure I had this in the bag," said Feysa.
Fellow Kenyan Brigid Kosgei, who set a then-world record of 2:14:04 in Chicago in 2019, continued her fine recent form with third place.
The 32-year-old -- a two-time winner in London, Tokyo and Chicago -- won last year's Shanghai Marathon and took this year's Tokyo title.
More than 55,000 runners competed over the 26.2-mile layout winding through the streets of Chicago.
Catherine Debrunner of Switzerland shattered her own women's wheelchair world record with a time of 1:33:16.