Barreto could be called up from Triple-A Nashville this weekend in the wake of Chad Pinder's hamstring injury, Susan Slusser of the San Francisco Chronicle reports.
The 21-year-old has been coming on with the Sounds, hitting .324 over the last 10 contests, and posting a solid .282/.328/.432 line over 67 games overall. Barreto was initially expected to be a post-All-Star-break callup, but Pinder's left hamstring strain, which could conceivably result in a disabled list stint, has significantly increased the chances of a much quicker debut.