The U.S. Open Cup will feature four MLS clubs in the semifinals after the Chicago Fire knocked out Louisville City, the last remaining outsider in the competition, with a 4-0 result on Wednesday.
Goals from Nemanja Nikolic and Aleksandar Katai had the Fire comfortably in front in the first half and a pair of late strikes put some gloss on the scoreline.
Alejandro Bedoya was on hand to poke home a rebound as the Philadelphia Union moved into the last four with a 1-0 win over Orlando City.
Houston Dynamo moved on past Sporting Kansas City with a 4-2 win.