That kind of example happens to every team, at several positions, every year. Even returning players often have wildly different projections and final numbers from one year to the next.
I project our offense from 2023 to 2024 will improve at C, 1B, 2B, SS, 3B. It will be about the same in LF & RF. It will drop at DH and CF.
I project our defense will improve slightly at C, 1B, 3B and LF. It will improve a lot at SS, 2B and hopefully CF (Rafaela wins the job). It may get worse in RF.
Our pitching is hard to project.
Gio & Bello vs Bello, Sale and Paxton at the 1-2 slots? Even?
Pivetta, Crawford & Houck vs Pivetta, Crawford & Houck at the 3-4-5 slots? Even?
Whitlock, Kluber plus 16 games of "openers" vs Whitlock, Murphy, Fitts & Walter? Even?
(Remember, even= sucks.)
The pen?
1/2: Jansen & Martin vs Jansen 3.63 in 45 IP & Martin 1.05 in 51 IP -- probably worse
3/4: Winckowski & Whitlock vs Wink 2.92 in 83 & Pivetta 3.07 in 56 IP-- likely worse
5/6: Campbell & Bernardino vs Bernardino 3.46 in 42 & Schreiber 3.83 in 45-- likely the same
7/8: Slaten & Mata vs Murphy 4.91 in 48 & Bleier 5.28 in 31-- maybe the same
after 8: Murphy, Fitts, Weissert, Z Kelly, Criswell, Walter, Guerrero -- maybe better
2023:
5.46 Llovera (30 IP)
4.26 Jacques (25)
6.26 Walter (23)
1.66 Crawford (22)
7.29 Brasier (21)
6.27 K Ort (19)
6.23 Garza (17)
9.45 Kluber (13)
6.55 Joely (11)
6.55 Robertson (11)