I was curious how Pratt's extension might compare to his theoretical path through arbitration. So I compiled a list of shortstops that have been in arbitration over the past 5 years (AI technically, so I'm sure I've missed a few players, but have enough of a sample to be in the ballpark). I calculated their Average WAR/year (this I did by hand) so I could put them in MIN, MID, and MAX tiers. 0-2 WAR=MIN, 2.1-4 = MID, 4.1+=MAX.
So that gives me a potential list of salaries for Pratt if he takes one of those three paths. For the "normal" path, I assumed he would be in AAA this year and gave him a max AAA salary. Then for the FA year, I dumped what was left of the $50.75M "budget" (his contract amount) to see how good of a deal this would be.
I used a 2% inflation for all numbers (salary and cost of WAR) to project out for 7 years. So, for today's FA cost of $8M/WAR, I used about $9.2M.
Year
Min
Mid
Max
Cooper MLB
AAA
$ 100,000
$ 100,000
$ 100,000
$ 6,343,750
1
$ 839,041
$ 839,041
$ 839,041
$ 6,343,750
2
$ 1,226,831
$ 1,226,831
$ 1,226,831
$ 6,343,750
3
$ 1,458,906
$ 1,458,906
$ 1,458,906
$ 6,343,750
Arb 1
$ 3,301,418
$ 4,266,587
$ 9,728,359
$ 6,343,750
Arb 2
$ 4,897,288
$ 9,605,503
$ 20,228,099
$ 6,343,750
Arb 3
$ 5,743,428
$ 11,332,009
$ 23,649,411
$ 6,343,750
FA 1
$ 33,183,087
$ 21,921,122
$ (6,480,647)
$ 6,343,750
WAR
3.6
2.4
-0.7
So there are 4 main outcomes:
Total Bust: Cooper doesn't even make it to Arbitration. This obviously is the worst-case scenario, but Cooper's defense keeps his floor high, so this is probably unlikely. But a Brewer Failure if that happens.
Min player: Here we are holding on to a SS that averages 0-2.0 WAR/year, and we chose to give him $33M in FA and hope he makes 3.6 WAR that year. This would be Joey Ortiz. Another Brewer Failure.
Mid Player: Now we have a SS that is giving us 2-4WAR/year. A one-year contract for $22M means we expect 2.4 WAR. This would be like signing Willy Adames for one more year. This feels like a break-even point, so I'll count this as a Brewer WIN.
Max Player: Clearly, what everyone is hoping for. The script flips a bit in this row and the Brewers have actually saved $6.5M through arbitration and get a FA year for "free". You have a 4+ WAR SS (like Gunnar Henderson) and saved money in the meantime. Brewer victory.
So what is the verdict? I'm pretty sure the Brewers are confident that Cooper won't be a bust (as am I). Being a max player is possible... but that one seems unlikely (though I'll bet on the MAX over being a Bust). So if the most likely outcomes are Min or Mid for Cooper, it seems like a pretty good contract for Cooper and just "ok" for the Brewers.
If Cooper is a high defensive SS with a light stick (his floor IMO), that is a clear win for Cooper. If he is average, he is going to be paid just a hair less than the market rate for his FA year. Not much of a risk on his part.
Caveat: I'm not sure if 2% is a great MLB inflation number (probably not). If salaries grow more than that, the trend will make the Brewer's decision look better in all outcomes.