The Giants cut the roster in camp from 42 down to 36 players. LH reliever Sam Selman, who I thought was a lock to open the season with the Giants, was optioned to the minors (presumably AAA). Infielder Jason Vosler, who seems to be the kind of versatile player FZ and Kap love, joins Selman. It's good to have quality backups in the system, and I should note that both players have options remaining.
Roster Resource shows veteran Wandy Peralta as the next LH reliever on the depth chart. They also like NRIs Shun Yamaguchi and Nick Tropeano as RH swingmen behind Tyler Rogers, Matt Wisler, and Reyes Moronta.