Breckinridge commanded four picked brigades, three selected from his own division and one of Martin L. Smith's Vicksburg brigades, the whole organized in two divisions, under Brigadier-Generals Charles Clark and Daniel Ruggles. Clark had the brigades of Brigadier-General Bernard H. Helm and Colonel Thomas B. Smith, of the 20th Tennessee, with the Hudson battery and Cobb's battery. Ruggles had the brigades of Colonel A. P. Thompson, of the 3d Kentucky, and Colonel Henry W. Allen, of the 4th Louisiana, with Semmes's battery. From right to left the order of attack ran, Helm, Smith, Thompson, Allen. Clark moved on the right of the Greenwell Springs road, and Ruggles on the left. Scott's cavalry was posted on the extreme left, four guns of Semmes's battery occupied the centre of Ruggles's division, while in Clark's centre were the four guns of the Hudson battery and one of Cobb's; the other two having been disabled in a panic during the night march before the battle. On the extreme right the Clinton road was picketed and held by a detachment of infantry and rangers and the remaining section of Semmes's battery.
To meet the expected attack, Williams had posted his troops in rear of the arsenal and of the town, occupying an irregular line, generally parallel to the Bayou Sara road, and extending from the Bayou Grosse, on the left, to and beyond the intersection of the Perkins and Clay Cut roads, on the right. On the extreme left, behind the Bayou Grosse, was the 4th Wisconsin, commanded by Lieutenant-Colonel Bean. Next, but on the left bank of the bayou, stood the 9th Connecticut. Next, and on the left of the Greenwell Springs road, the 14th Maine. On the right of that road was posted the 21st Indiana, under Lieutenant-Colonel Keith, with three guns attached to the regiment, under Lieutenant J. H. Brown. Across the Perkins and Clay Cut roads the 6th Michigan was formed, under command of Captain Charles E. Clarke, while in the rear of the interval between the 6th Michigan and the 21st Indiana stood the 7th Vermont. The extreme right and rear were covered by the 30th Massachusetts in column, supporting Nims's battery, under Lieutenant Trull. On the centre and left were planted the guns of Everett's battery, under Carruth, and of Manning's 4th Massachusetts battery.