The merry-go-round continues for the New York Mets bullpen. The team announced four roster moves Monday ahead of its three-game series with the San Francisco Giants.

RHP Michael Tonkin (1-2, 6.00), who started the season with the Mets, pitched for Minnesota and then returned to New York, has been designated for assignment. Lefty Josh Walker was called up from Triple-A Syracuse. Walker threw three scoreless innings in spring training. In 10 innings with the Mets last year, he had an 8.10 ERA, struck out 12 and walked six.

RHP Grant Hartwig (two earned runs in three innings) was optioned to Syracuse. RHP Sean Reid-Foley, who has yet to pitch this season, has been reinstated from the injured list. In his Mets career, Reid-Foley is 2-2 with a 4.93 ERA in 38.1 innings of work. He’ll likely be the long-relief option, his former role with the team. Reed Garrett has been used in a similar role this season but has appeared in higher leverage situations as of late the more he’s excelled, and will be called upon to do so more.