Barreto was called up from Triple-A Nashville on Friday, Susan Slusser of the San Francisco Chronicle reports.
It's Barreto's third big-league stint this season, with this latest callup stemming from the placement of Matt Chapman (hand) on the disabled list. Barreto is still looking for his first big-league hit of 2018, and he was slashing .234/.337/.448 with 18 extra-base hits (10 doubles, one triple, seven home runs) and 20 RBI across 181 plate appearances at Nashville.