Golf ball

A golf ball comprising a spherical core and at least one cover layer covering the spherical core, wherein the spherical core is formed from a rubber composition containing

• (a) a base rubber,
• (b) an α,β-unsaturated carboxylic acid having 3 to 8 carbon atoms and/or a metal salt thereof as a co-crosslinking agent,
• (c) a crosslinking initiator including 2,5-dimethyl-2,5-di(t-butylperoxy)hexyne-3, and
• (d) a carboxylic acid and/or a salt thereof, excluding an α,β-unsaturated carboxylic acid having 3 to 8 carbon atoms and a metal salt thereof,
• a content of (c) the crosslinking initiator is 0.2 part to 0.8 part by mass with respect to 100 parts by mass of (a) the base rubber,
• the spherical core has a diameter in a range from 34.8 mm to 42.2 mm and a compression deformation amount in a range from 2.8 mm to 6.0 mm when applying a load from 98N as an initial load to 1275N as a final load to the spherical core, and
• when JIS-C hardness of the spherical core is measured at points located at distances of 0% (core center), 37.5%, 75.0% and 100% (core surface) from the core center of the spherical core,
• a hardness difference (Hs−Ho) between a surface hardness (Hs) thereof and a center hardness (Ho) thereof is 28 or more,
• a ratio ((H37.5−Ho)/(H75.0−Ho)) of a hardness difference (H37.5−Ho) between a 37.5% point hardness (H37.5) and a center hardness (Ho) to a hardness difference (H75.0−Ho) between a 75.0% point hardness (H75.0) and a center hardness (Ho) is 0.39 or less, and
• the compression deformation amount (D (mm)) of the spherical core and the 37.5% point hardness (H37.5) satisfy a relation of H37.5≦−9×D+95.