Well..... not so fast. The only thing that is clear is that if you hold a winning ticket that can not be cashed at the retailer, there is a substantial restriction. As such, until the lottery verifies your claim and makes the funds available to you, you don't have income.
What has never been litigated (or if it has I am not aware) is the instance where you intentionally hold onto the ticket until such time that the funds would not be available until the next tax year. There are other cases that deal with attempts to delay receipt of income that would probably tell us that you can't do that.
Now try this one on for size: You are on vacation in NY and buy a megamillions ticket. You return home to CA and completely forget about the ticket until a few months later (new tax year) when you open the luggage bag to go on a trip and find the winning ticket. No intention on your part to defer income. ????