1. Ben Brown
Ben Brown seemed to be on track for cementing his spot in the Chicago Cubs starting rotation for the long term when he made his Major League debut earlier this season.
Through 15 appearances this season, 8 starts, Brown posted a 3.58 ERA while averaging over 10 strikeouts per 9 innings pitched. Brown was one of the Cubs' top pitching prospects at the start of the season and his initial run at the Major League level seemed to be worthy of the hype.
Unfortunately, Brown hasn't pitched since June 8 as he has been dealing with a neck issue. The hope is that by the time that the 2025 season starts, Brown is ready to go.