A golf ball comprising an inner core having an outer surface and a geometric center and being formed from a substantially homogenous rubber composition, the rubber composition comprising a base rubber and a resorcinol such that the geometric center has a hardness of 50 to 60 Shore C and the outer surface has a hardness of 85 to 95 Shore C. An outer core layer is disposed about the inner core and has an outer surface having a hardness of 50 to 75 Shore C, an inner surface having a hardness of 51 to 76 Shore C, and is formed from a substantially homogenous composition. A cover layer is disposed about the outer core layer. The hardness of the inner core outer surface is greater than the hardness of the geometric center to define a positive hardness gradient of greater than 20 Shore C, and the hardness of the outer core outer surface is lower than the hardness of its inner surface to define a negative hardness gradient of −1 to −5 Shore C.