Barreto will be called up to replace the injured Chad Pinder (knee) Saturday, the San Francisco Chronicle reports.
Barreto got his first taste of the big leagues last season, struggling through 25 games with a .197/.250/.352 line and a 43.4 percent strikeout rate. The 22-year-old fared much better at Triple-A Nashville, hitting .290/.339/.456 in 111 games. He has the potential to one day hit for average and power while stealing a fair number of bases, though it remains to be seen whether he's big-league ready this time around. Barreto's stay with Oakland could be short, as Pinder's injury appears to be minor, but he could stick around if he impresses right away.