Multi-piece solid golf ball

A multi-piece solid golf ball comprising a multi-layer core each having at least an inner layer core and an outer layer core, a single-layer intermediate layer, and a single-layer cover, wherein the inner layer core is formed of a rubber composition, the intermediate layer and the cover are both formed of a resin composition, and a relationship among an initial velocity of the inner layer core, an initial velocity of an entire core, an initial velocity of a sphere (intermediate layer-encased sphere) obtained by encasing core with the intermediate layer, and an initial velocity of a sphere (ball) obtained by encasing the intermediate layer-encased sphere with the cover satisfies the following three conditions:

• (initial velocity of ball)<(initial velocity of intermediate layer-encased sphere)
• (initial velocity of intermediate layer-encased sphere)−(initial velocity of entire core)≤0.70 (m/s)
• (initial velocity of entire core)−(initial velocity of inner layer core)≥0.20 (m/s)
• and a specific gravity of the intermediate layer is at least 1.05, and a deflection (mm) when the golf ball is compressed under a final load of 1,275 N (130 kgf) from an initial load of 98 N (10 kgf) is not more than 3.0 mm, and
• wherein the following condition is satisfied:
• 1.00≤(initial velocity of intermediate layer-encased sphere)−(initial velocity of inner layer core)≤1.60 (m/s).