JUNE 15-18, 1864:
June 17th
Most of the Union effort was focused just south of the fighting on June 15th and their poorly coordinated attacks offset the numerical advantages of the Northern forces by allowing Beauregard to concentrate his troops where needed.
Beauregard had been busy telegraphing Lee for the last several days for support from the main Confederate force near Richmond. Lee was then convinced of Grant's real intentions and rushed reinforcements to Petersburg.