The first shots of the battle were fired early on the morning of October 8. Finding that there were algae-covered pools of water in the otherwise dry bed of Doctor's Creek, troops from the 10th Indiana advanced to take advantage of them. They encountered the forward men of the 7th Arkansas and some shots were exchanged. At 2 a.m., Buell and Gilbert, the III Corps commander, ordered newly promoted Brig. Gen. Phil Sheridan to seize Peters Hill; Sheridan started off with the brigade of Col. Daniel McCook (the younger brother of the I Corps commander). Sheridan seized the hill, driving the Arkansans back to the main line of their brigade, but continued to push across the creek. Liddell's brigade could not check the momentum of Sheridan's thirsty soldiers and Buckner, Liddell's division commander, was ordered by Polk not to reinforce him, but to pull his brigade back. Polk was concerned about starting a general engagement to the west of the Chaplin River, fearing he was outnumbered. Meanwhile, on the Union side, a nervous Gilbert ordered Sheridan to return to Peters Hill.