Hart's Arkansas Battery were advanced to a position at the rifle pits, near the river. Meanwhile, McClernand's men were being offloaded from their transports about or from Arkansas Post, with the process beginning at 5 p.m. Morgan's corps was to advance directly, while Sherman's was to swing around and attack from the northwest. That same day, the Union warships bombarded the Confederate works. On the morning of January 10, Sherman's men finished unloading around 11 a.m. One of Morgan's brigades, under the command of Colonel Daniel W. Lindsey advanced, and took up a position on the other side of the river in order to prevent riverine reinforcements from reaching the Confederates. As Sherman was beginning his flanking movement with Steele's division, McClernand determined that a more direct path looked promising, so Stuart's division was rerouted along it. Steele's men, in turn, found that their flanking path was blocked by an impassable swamp, and that division had to backtrack its path anyway. Porter's ships were also busy that morning, as the ironclads and the gunboat USS Lexington fired on Fort Hindman, while the gunboats USS Black Hawk and USS Rattler fired on the rifle pits. Around 2 p.m., Churchill learned of Sherman's flanking maneuver and decided to withdraw his forces from the outer line, which was quickly reoccupied by Stuart's men. One Union brigade pressed the Confederate retreat until it came under fire from Confederates in the main fort. Morgan's men advanced as well, and the Union lines were filled out with Stuart's men on the right approaching Post Bayou, and Smith's on the left. Confusion during the movements into these positions led to delays. Before the delays had occurred, McClernand had told Porter that his men would be ready to attack at 2 p.m. At 5:30 p.m., McClernand told Porter that his men were finally ready, and the Union vessels advanced towards the fort to bombard it. The three ironclads moved in to close range and were each assigned one of the heavy Confederate guns. Lexington and Black Hawk provided supporting fire. The shooting from the naval vessels was effective, and most of the horses within the Confederate position were killed. Rattler was assigned to move past the fort and bombard it from the other side, but it was damaged when it fouled on a piling in the river and had to withdraw. The Confederate batteries had been silenced, but