The Pirates acquired Nunez and right-hander Johan Oviedo from the Cardinals on Monday in exchange for left-hander Jose Quintana and right-hander Chris Stratton.
Nunez had spent all of the 2022 season at Double-A Springfield, churning out a .255/.360/.463 slash line to go with 17 home runs, 66 RBI, 51 runs scored and four stolen bases in 85 games. The Pirates will likely have the 21-year-old first baseman report to Double-A Altoona to begin his time in the organization.