Conner Mantz came into the Bank of America Chicago Marathon with the goal of setting a new American record, and that’s exactly what he did. After finishing the Boston Marathon in 2:05:08 earlier this year, Mantz completed the Chicago course in an unofficial time of 2:04:43, smashing an American record that had stood for more than two decades. ⁠ ⁠⁠ #connermantz #chicagomarathon #running #marathon #chicago #runner | NBC Chicago