Downs enters the coaching ranks after a 17-year pro-playing career, which includes three seasons at the Major League level.
The 32-year-old batted .262 with two home runs, 33 RBI, 36 runs, 72 hits, 13 doubles, two triples, and a .346 on-base percentage in 74 games with Long Island in 2019.
Stassi first made "The Show" as a member of the Phillies, collecting his first major league hit, a solo homer, off of then-New York Met pitcher Addison Reed on April 10, 2017.
Tomlin coached under current Long Island manager Wally Backman in 2010 with the Cyclones, the Mets' short-season Single-A affiliate of the New York-Penn League (NYPL), helping the club reach the league finals.
With Niese, the Ducks now have five ex-Mets on their roster -- three players (Niese, Matt den Dekker and Kirk Nieuwenhuis) and two coaches (Wally Backman and Ed Lynch).
Ed Lynch reunites with LI Ducks manager Wally Backman.