The New York Mets will designate starting pitcher Matt Harvey for assignment, general manager Sandy Alderson announced on Friday.

The team had requested Harvey accept a minor league assignment, but he refused, Alderson said.

"This was a long time coming," Alderson said at a news conference on Friday. "This is something we've tried to address, we've struggled with, we've wrestled with over two managerial regimes."

Harvey was a first-round pick by the Mets in 2010. He debuted for New York in 2012 and quickly reached star status, recording a 2.73 ERA over 59.2 innings pitched. One season later, Harvey was an All-Star, registering a 2.27 ERA while striking out 191 hitters.

Harvey underwent Tommy John surgery in October 2013 and missed the entire 2014 season. He returned in 2015 and helped the Mets reach the World Series. But, Harvey regressed quickly. He battled through injuries in 2016 and 2017, making just 35 starts.

This season, Harvey has struggled tallying a 7.00 ERA. He was moved to the bullpen after surrendering six runs in an April 19 start against the Braves, but never found a rhythm in a relief role, allowing seven runs in four appearances.

"The move to the bullpen was dramatic in itself," Alderson said. "I think that, at this point, pragmatism, realism far outweighed other considerations."

Mets manager Mickey Callaway said he felt as if he failed Harvey.

"We thought, from our evaluation in spring training, we could get him to where we wanted him to be and we didn't," Callaway said. "We tried things. It's more of a feeling that, when your players don't succeed, you feel it."

The Mets opened 2018 with an 11-1 record but have since fallen to the back of the pack as they currently stand at 17-12.