I think the following is accurate, but welcome corrections if I've gotten anything wrong.
They have 7 guys signed for next year. According to
Sportrac, this is how much their salaries account for in terms of cap calculations:
Price - $31m
JDM - $22m
Sale - $25.7
X - $20m
Eovaldi - $17m
Pedey - $13.75
Vazquez - $4.5
That's a total of ~$134m. Benefits and minor league contracts cost ~$17.5m. That means that the Sox go into the offseason with ~$151.5m already spoken for.
The
2020 tax levels are $208m, $228m, and $248m.
Mookie, ERod, Benintendi, JBJ, Barnes and Workman all will be arb eligible. Devers is still under club control without arb eligibility.
Now you start prognosticating:
Mookie made $20m this year. Let's say the Sox play hardball in arbitration, point to his "down" year, and he stays at $20m.
Let's say ERod, Benintendi, JBJ, Barnes and Workman wind up making $20m as a group.
Devers will have to get a raise, but only enough to keep him moderately happy. Let's call that $1m.
Assume you fill in first and second with Chavis and Lin, who make a total of about $1m.
Let's further assume that they need to keep about $10m free to give them room to maneuver during the year.
Even in this best-case scenario (which includes giving Mookie no raise, not doing much to keep Devers happy, and living with a right side of the infield of Chavis and Lin), the Sox would be at around $203m in terms of a tax number before they add a starter, top-line reliever and a bench/bullpen (assume 5-6 more pitchers and 3-4 bench guys). And presumably DD will remain under strict orders not to exceed the $248 tax threshold.
So he's got $45m with which to fill 9 spots. That is an unenviable task.
JDM could opt out, which would throw some of this analysis out the window. JDM's money would allow them to pursue another solution at first or second or give Mookie his extension.
If JDM stays, it's hard to avoid the fact that trading Mookie this off-season is an obvious means to resolving a lot of issues. He could land them good young players who can fill areas of need, and it seems hard to imagine they'll be able to afford to pay him in 2021 given what he'll demand and what their salary structure looks like.
So the question may ultimately be: do you trust DD to make the decision whether or not to trade Mookie? And do you trust him to extract max value for Mookie if he moves him?
Edited to reflect comments below