Emily Sisson sets American record at Chicago Marathon, landing in second place behind defending champ Ruth Chepngetich

Kenyan Ruth Chepngetich won the Chicago Marathon on Sunday with a time of  2:14:18, followed by Emily Sisson, whose unofficial time crushed the women's marathon record set 16 years ago in London. 

Chepngetich, the defending Chicago Marathon champion, set an early lead but told ESPN she had hoped to break the world record, coming up 14 seconds short on Sunday. 

"I wanted to break the world record ... but I'm happy," Chepngetich said. "Next year I'm ready to come back again."