The Pirates promoted Griffin from High-A Greensboro to Double-A Altoona on Sunday, Noah Hiles of the Pittsburgh Post-Gazette reports.
Griffin will receive his second promotion of the season after a dominant showing during his time in the South Atlantic League. Over 51 games with Greensboro, Griffin slashed .325/.432/.510 with seven home runs and 33 stolen bases across 234 plate appearances. Since being selected with the No. 9 overall pick in the 2024 First-Year Player Draft, the 19-year-old shortstop has quickly established himself as arguably baseball's top prospect, and he could be on track to make his MLB debut at some point in 2026.