We can't ever remember seeing this happen in an elite marathon and doubt we'll ever see it again.

We share our six biggest storylines with you and introduce you to the new men's favorite - Reuben Kipyego - whom we just learned was running the race today.

Just as he did in Boston earlier this year, Lawrence Cherono won a thrilling sprint finish for the title today in Chicago. Meanwhile, former NOP teammates Mo Farah and Galen Rupp both struggled but 10 Americans broke 2:12.

Paula Radcliffe's legendary 2:15:25 world record is history after 16+ years.

American record alert. Jordan Hasay says she's going out in 70 flat.

Jonathan Gault has a hard-time believing one key answer Rupp gave at today's press event. When asked when did he learn that Salazar had been charged by USADA, Rupp said, “I read about it on the news, I think like everybody else.” As for what type of shape Rupp is in, Rupp himself wants to know. “I’m kind of wondering about it too, to be honest,” Rupp said.

The world's best marathoner Brigid Kosgei is racing Chicago and that means Paula Radcliffe's 17-year-old course record of 2:17:18 is in jeopardy. Could Deena Kastor's American record also fall?

How will Rupp do in his first race since last year's Chicago and in his first since Alberto Salazar's ban? Should defending champ Mo Farah be considered the favorite or should that honor go to Boston champ Lawrence Cherono?

Chronic foot issues led to flare-ups in other areas, which caused the 36-year-old to withdraw ahead of the race on October 13. He still plans on racing the Olympic Trials in February.

We break down what it all means as we we get closer to the 2020 US Trials. Plus, why we think Berlin might be a better option. *MB: 2019 Chicago Marathon US field is out: Cragg, Derrick, Ritz Join Rupp & Hasay

Does this mean that Farah is out of the 10,000 at Worlds since it takes place one week before Chicago? Jordan Hasay is also going to the Windy City as well.

The press conference today in Chicago was fascinating. Can a 1:44 800 guy really run 2:05? Can an American not named Galen Rupp run 2:10? Can Laura Thweatt take the next step?

Both men downplayed speculation that Sunday's race would serve as a huge duel between former friends. "We still have a great relationship," Rupp said. Plus Farah reveals he hopes the pacers go out in 62 flat.

Jordan Hasay and Amy Cragg will be missed but three sub-2:20 women including the 2018 Dubai and Tokyo champs are racing as are Laura Thweatt and Gwen Jorgensen.

Six years ago, they were training partners, the best of buds and on top of the world after going 1-2 in the 10k at the Olympics. Now they are rivals, and this Sunday in Chicago, Mo Farah and Galen Rupp will be quare off for the first time at the 26.2 mile distance.

We try and map out Galen Rupp's marathon career through 2021.

Two of America's biggest marathon stars don't know what to make of Galen Rupp's win in Chicago due to the ongoing USADA investigation. Meb Keflezighi said he was happy for Rupp and Salazar but added "there's a lot of speculation going on and I would love to know what’s going on and how far it’s gotten." *MB: Breaking: Shalane and Meb react to Galen Rupp's Chicago Win