They've pretty much already signaled they're basically done, they're not going to suddenly spend another $30 million somewhere, if he stays it's a little less (And other money is coming off). The only time it becomes an issue is if he does revert to the mean and put up 3+ fWAR and you don't want to just let that production walk next offseason. If they were concerned with that, they certainly could've offered more years to Alonso, at a lower rate. I'm sure he would've been more open to deferrals too, if the contract length was longer.