“There’s ways to help guys in the bullpen from the way they attack, the mentality you need to have out of the bullpen, and it became obvious that maybe that wasn’t the case with Matt,” Mets Manager Mickey Callaway said.

So John Ricco, the Mets’ longtime assistant general manager, the pitching coach Dave Eiland, Callaway and Alderson met with Harvey on Friday afternoon and explained how going to the minors could help, in part by giving him a change of scenery, away from the pressure of the majors. Callaway pointed out that other struggling pitchers, such as the former Toronto ace Roy Halladay, had gone down to the minors and benefited from the move.

Alderson said he did not expect Harvey to accept the offer.

Because Harvey has been in the major leagues for at least five years, he was allowed to decline the assignment based on collectively bargained rules. Harvey did, and will end up in another team’s uniform.

Harvey’s best seasons were in 2013 and 2015, when he posted a 2.50 E.R.A. over 55 starts. His struggles since have raised his career E.R.A. to 3.66 over 639 innings. His career record with the Mets is 34-37.

He is owed the remainder of his 2018 salary of $5.6 million, most of which the Mets will have to pay unless they work out a trade. Despite his weak record of late and his checkered off-the-field reputation, Harvey might still draw interest from other teams if he is released. He could sign for a prorated portion of the major league minimum of $545,000.

“My guess is there are people out there who would take a shot at him,” Alderson said.

After Harvey showed promise in spring training this year, his arm got stiffer and “his stuff went backwards,” Eiland said. Harvey pitched like a player who thought he still had a dominant fastball-slider combination, which, in reality, he did not.

“When you’re trying to win major league baseball games, it’s hard to have a guy on your staff rehabbing,” Eiland said. “It’s not fair to him. It’s not fair to the team.”