Jones will take the rotation spot of Julio Rodriguez, who went on the Baysox disabled list this week after allowing six runs and six hits with seven walks in just 2 2/3 innings on Monday at Richmond.
The 22-year-old Jones, drafted by the club in the ninth round out of Mississippi State in 2011, pitched well in his opening start for Frederick, going six innings and giving up just three hits and one run against Salem last Friday at Harry Grove Stadium.
Jones went 8-7 with a 2.72 ERA over 28 games with nine starts between Single-A clubs Delmarva and Frederick last season. When he moved to Frederick in mid-July, he also moved into a starting role and did quite well, going 7-1 with a 2.80 ERA for the Keys. He had a 2.15 ground-to-air out ratio and held right-handed batters to a .238 average.
Kevin Gausman is expected to start Thursday night's 7:05 p.m. game for the Baysox, which will be their home opener at Prince George's Stadium.
With this move, now Triple-A Norfolk, Bowie and Frederick will be using five-man rotations while Delmarva remains in a six-man.