Edward Ord
Under Grant's order, on the night of March 27–28, Major General Edward Ord, quietly moved units from the Army of the James, including two divisions of Major General John Gibbon's XXIV Corps, a division of Major General Godfrey Weitzel's XXV Corps and Brigadier General Ranald S. Mackenzie's cavalry division from the Richmond lines to fill in the Petersburg lines to be vacated by the II Corps when they moved to support Sheridan. Confederate Lieutenant General James Longstreet's corps defending the Richmond lines failed to detect Ord's movement, thus limiting the number of men Lee could move to counter the movement of Grant's forces without fatally weakening the Richmond lines.