"Since they still needed a touchdown, Nolan with this move essentially made the statement that the 49ers recovering an onside kick was more likely to happen than the 49ers converting a fourth-and-10."

Even if Nolan actually believed that the success rate of an onside kick > success rate of 4th and 10, you still have to factor in the huge field position advantage of going for it on 4th and 10. All in all, it just boils down to a horrible decision when you think about it.

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