What does Santander offer that O'Neill doesn't? O'Neill is much better against lefties (even though Santander is also decent). Santander has been much better against righties, but would also be moving to a park that blunts LH pull power. Neither player is a good fielder. What am I missing?
Consistency and availability would be my short, glib answer. More thought out:
My take on this - and I know that this always opens up a can of worms - but it is something I'd look at as a GM. Obviously, all players and any players can get hurt at any time. Some players tend to be more frequently available than others. Looking at the last four years (and they're the same age):
O'Neill has played in 419 total games, for an average of 105 per year (and his high water mark was 138 games 4 seasons ago, in 2021, since then he has not played 115g in any season).
Santander has played in 570 total games for an average of 143 per year (and his low water mark was also 4 years ago, at 110g - the last 3 he's been over 150 each year).
As to how he'd fit in Fenway Park, for starters, I agree that 2024 was an outlier for Santander - plenty of guys have good contract years that don't look much like the prior several (same as Tyler O'Neill, for what it's worth). I'm not going to pretend to know what launch angle a fly ball needs to be sent at in order to clear the Wall as opposed to a single or a double, I have no idea, but looking at an overlay of Santader's spray chart (and I chose 2023 because I agree that 2024 was an outlier) it looks like a lot of his "outs" would turn into much more positive events at Fenway Park, especially those hit to left and left center.
https://baseballsavant.mlb.com/illustrator?playerId=623993&playerType=batter&name=Anthony Santander&tabSelection=0&shape=square&shapeName=Square (Instagram)&subTitle=&chartType=sprayChart&chartName=Spray Chart&pitcherThrows=&batterStands=&plateAppearanceResults=[]&pitchTypes=[]&seasonType=["R"]&pitchResults=[]&facingPlayer=[]&balls=[]&battedBallType=[]&years=[2023]&strikes=[]&outs=[]&selectedGames=[]&homeTeam=[]&awayTeam=[]&vsTeam=[]&exitVelocityGT=0&exitVelocityLT=125&pitchVelocityGT=0&pitchVelocityLT=105&launchAngleGT=-90&launchAngleLT=90&perspective=catcher&venue=3
Besides that, he does offer at least "some" protection in the event of another injury to Casas. Santander has appeared in ~15 games at 1b in his career, most coming in the last two seasons. O'Neill to my knowledge has never played the position.
While I will (admittedly too liberally for some) use the injury prone label to someone that has missed a ton of time over the course of their career, especially recently in the case of current players (Ellsbury, Stanton, Story, O'Neill) I'm not one to throw the injury prone label on someone for one instance (Casas), HOWEVER because he did miss such significant time, having someone that could slide from DH (where Santander would be in my plan) to 1b would be helpful a benefit, I'd think.
In summation, I'd far rather have 4 years of Santander than 3 of O'Neill (and 1 of O'Neill). But I know other people disagree on the way to use and spend on a DH. If Breslow and company are committed to the idea of Devers staying at 3b for the next several years, 4 years on Santander would put Devers at the DH spot entering his age 32 season - which I'd have to assume even those that think Devers should stay at 3b - would concede would be a good time to have him focus on just hitting.
Duran - CF (L)
Story - SS (R)
Devers - 3b (L)
Santander - DH (R)
Casas - 1b (L)
Abreu - RF (L)
Wong - C (R)
Anthony - LF (L)
Campbell / Grissom - 2b (R)
Looks good to me. Plus, if Anthony isn't ready to break camp with the Sox (which I think he will be, but assume he's not) then Santander plays LF until he is.