The move was made Tuesday two days after the Hoops' 5-1 loss to the Los Angeles Galaxy dropped their record to 2-3-3 this season, good for fourth in place in the MLS Western Conference.
FCD's third loss in its last four games came before the biggest crowd ever at Pizza Hut Park in Frisco, Texas.
"Obviously, this is a difficult decision for me since it was my choice to give Steve this opportunity," said Hoops president and general manager Michael Hitchcock on the team's Web site. "I feel that the team wasn't heading in the direction we had planned and believe it was in the best interest of the club to make a change in leadership at this time."
Last season, the Hoops, under Morrow's leadership, advanced to the MLS Cup Playoffs for the 10th time in league history.