Mets GM Sandy Alderson says Matt Harvey's exit was "a long time coming" as the organization has spent a lot of time attempting to rectify it. (1:38)

NEW YORK -- The New York Mets designated Matt Harvey for assignment Saturday, marking an abrupt and stunning end to the tenure of a pitcher who was considered one of baseball's budding stars and the future face of the organization upon his arrival in 2012.

Mets general manager Sandy Alderson said Friday the team made the decision after Harvey refused a demotion to the minor leagues to work out his problems. The Mets recently moved Harvey to the bullpen, but he struggled with the transition and allowed five runs in an 11-0 loss to the Atlanta Braves on Thursday at Citi Field.

Alderson, assistant GM John Ricco, manager Mickey Callaway and pitching coach Dave Eiland met with Harvey at 3:15 p.m. ET Friday and asked him to consider an assignment to the minors. They told Harvey to take a few hours to talk to his agent, Scott Boras, and make a decision. But Harvey declined quickly enough for Alderson to make the DFA announcement by 4 p.m.

The Mets have seven days to either trade Harvey or release him and allow him to find a new team as a free agent.

Alderson said the move marks "the end of an era."

Harvey, 29, was the seventh overall pick in the 2010 MLB draft out of the University of North Carolina. He went 9-5 with a 2.27 ERA in 2013, started for the National League in the All-Star Game and was anointed the "Dark Knight of Gotham."

But Harvey's career stalled after Tommy John surgery and thoracic outlet syndrome surgery, and he was at the center of numerous off-field controversies. The latest came earlier this week when the New York Post reported that he was seen partying in Los Angeles during the Mets' West Coast swing.

Former Mets ace Matt Harvey had to undergo surgeries in 2014 and 2016. AP Photo/Julie Jacobson

"I think we've tried to find some other solution over a fairly long period of time,'' Alderson said. "This was a long time coming. It's something we tried to address, we struggled with, and we wrestled with over two managerial regimes. The move to the bullpen was dramatic in itself. I think at this point, pragmatism and realism far outweighed other considerations.

"Matt's gone through two serious and career-threatening injuries, and he made every effort to return to a championship level. Obviously, there were challenges along the way for him and for us. But those challenges were always worth meeting, not just because of his ability. Matt is an appealing, likeable and vulnerable individual. In spite of the issues, I really like Matt. We're going to miss him, in many ways.''

Harvey's velocity peaked at 96 mph in 2015, and he logged a 2-0 record with a 3.04 ERA and 27 strikeouts in 26 2/3 postseason innings when the Mets advanced to the World Series.

But his velocity gradually declined after thoracic outlet syndrome surgery, and he was registering 92.6 mph on the radar gun this season. The Mets hoped his fastball might tick upward in more limited exposure in the bullpen, but that never happened.

Callaway said he and Eiland were both disappointed that Harvey failed to make more progress this spring. Harvey's struggles were reflected in a 0-2 record, a 7.00 ERA and a 1.56 WHIP in eight appearances as a starter and reliever.

"It became evident to Dave and myself that him getting to where he needed to be out of the bullpen probably wasn't something that was realistic,'' Callaway said. "I thought the route that Roy Halladay and Cliff Lee took when they went all the way down to 'A' ball and kind of rebuilt themselves after 60-70 games in the big leagues was probably a more appropriate route to help Matt Harvey the best we could.

"It's tough for both of us. We feel like we failed Matt Harvey. I think our job is to help every player, and it's not a good feeling when you can't.''

Mets outfielder Jay Bruce, speaking to reporters after an 8-7 loss to Colorado at Citi Field, said he wasn't surprised that Harvey declined to go to the minor leagues.

"I could not imagine him accepting an assignment," Bruce said. "You pitch and play long enough, and you've earned the right to refuse an assignment. I don't know of many guys in his shoes who would have accepted it. I feel like he thinks he can have a chance somewhere else to kind of get a fresh start and a clean slate, and he's probably looking forward to that.

"Matt's had a lot of ups and downs here -- some of the highest ups and the lowest downs. I just wish him the best, I really do. This happens to a lot of people. It's just a little more of a bombshell in New York because of the history and the circumstances here. You see it all the time, where guys get a new start and they thrive."

In a text to ESPN, Boras expressed confidence that Harvey can succeed in his road back to becoming an effective big league starter. But Harvey's comeback will have to take place somewhere other than Citi Field.

"We feel Matt is a starter that needs to work on four pitches,'' Boras said. "In the bullpen, a pitcher tends to focus on two pitches to get back to the rotation. Thoracic outlet syndrome is difficult, as location of pitches and feel to pitch is the issue.

"We're very pleased Matt is healthy and with more-than-needed MLB velo. We have a lot of clay to work with to build the starter sculpture.''

The Mets recalled reliever Hansel Robles from Triple-A Las Vegas.