Sanders is with the Pirates' taxi squad in Arizona prior to Wednesday's game against the Diamondbacks, Colin Beazley of the Pittsburgh Post-Gazette reports.
It's not clear what the Pirates' plans are for Sanders, but the 29-year-old right-hander could be deployed out of bullpen at some point during the team's road trip. He's spent the majority of the season in Triple-A but has appeared in three major-league games, allowing four runs on four hits and two walks while striking out four across three innings.