The Colorado Rapids fired coach Pablo Mastroeni on Tuesday in his fourth season in charge.
First team assistant Steve Cooke will take over on an interim basis, the MLS club said in statement, with assistant Conor Casey and goalkeeper coach Chris Sharpe also remaining in their roles.
A source told ESPN FC that the decision was made by the Rapids' interim general manager Padraig Smith with the support of ownership. Smith has been the club's sporting director since 2015 but only took on his new role as GM three weeks ago.
The Rapids are 10th in the Western Conference, level on points with last-placed expansion side Minnesota United and 10 points off the final playoff spot.
Colorado is without a win in six games, losing twice and drawing four times since the last victory on July 1.
Mastroeni, 40, took over the Rapids ahead of the 2014 season. They finished last in the West in his first two years but showed a massive improvement in 2016, finishing second.
But it was back to the bottom this year, and the club decided to move in another direction with 12 games remaining.
"We would like to thank Pablo for his contributions to this organization, both as a player and as head coach," Rapids sporting director Padraig Smith said.
"He has been dedicated to the growth of this club for over 15 years and played an instrumental role in many of our successes.
"Unfortunately, we have fallen short of our expectations, and this decision was taken in the best interest of the players and the organization as a whole."
Before entering coaching, Mastroeni played for the Rapids from 2002-2013 and made 65 appearances for the U.S. national team.
ESPN FC's Jeff Carlisle contributed to this report.