There aren't really severe injuries for hitters that would take him from millions to out of the league, like there can be for pitchers. Sure, there are some examples, like Rocco Baldelli, but it's far less common than pitchers. I do obviously agree that the safest route, that still pays him very well, is signing a deal that buys out a couple years of free agency, and he still can get a monster contract. But he'll be delaying that monster contract and not optimizing what he could earn if he just goes year-to-year and then hits FA as a 26 year-old.If he gets a severe injury, he gets nothing.
He could still sign a 200+ million dollar contract at age 28.
If he turns down a deal, it would be a monster gamble..and a pretty dumb one at that.
It would depend on exactly what dollar figures the extension is for to see if it's a good gamble or not. If we go somewhere between Tulo and Longoria, then we're talking about $0.65M, $1M, $1.5M, $4M, $6M, $8M, maybe bumped up a bit for a few years worth of inflation, to cover his service time and then a discount on a couple years of free agent prices, let's say about $12M and $15M? Tulo signed for $10M and $15M, Longoria for $11M and $11.5M. So that would be a total of about 8/$48M. $21M via arbitration and $27M in the two free agency years.
If he goes year-to-year, he'll probably get near the minimum for his pre-arb years, so something like $550k, $600k, $650k, or about $1.75M over the three years. Through arb, he'll probably get something like $3.5M, $6.5M, and $10.25M (the $3.5M and $6.5M are very close to what Jones got in his Arb-1 and Arb-2 years). So that's about the same as the Longo/Tulo extensions locked them in for ($1M more in this estimate). If he's really, really good, then you'll see those arbitration numbers go through the roof and he can make maybe as much as double of that estimate.
It just depends on how much is the security worth to you or if you wanna roll the dice and try to make even more but without the guarantee. I could see him favoring either approach.