On October 29, 1996, in a cost-cutting move, the Expos traded Fassero and Alex Pacheco to the Seattle Mariners in exchange for Chris Widger, Matt Wagner and Trey Moore.

Fassero enjoyed some stability during his time with the Mariners, but after a mid-season trade to the Texas Rangers in 1999, he would wind up playing on eight different teams in only seven seasons.

[1] Fassero said that he would not be ready in time, and was subsequently released by the Rockies due to what then-manager Clint Hurdle called "philosophical differences".

[1] He almost immediately signed with the Arizona Diamondbacks, but he only made one appearance with the team, pitching one perfect inning in relief.

[2] In the winter of 2008, though, Fassero pitched with Mayos de Navojoa in Liga Mexicana del Pacífico before he finally retired for good.