Gen. Lee arrived on the battlefield at about 2:30 p.m., as Rodes's men were in mid-attack. Seeing that a major assault was underway, he lifted his restriction on a general engagement and gave permission to Hill to resume his attacks from the morning. First in line was Heth's division again, with two fresh brigades: Pettigrew's North Carolinians and Col. John M. Brockenbrough's Virginians.^[31]

Pettigrew's Brigade was deployed in a line that extended south beyond the ground defended by the Iron Brigade. Enveloping the left flank of the 19th Indiana, Pettigrew's North Carolinians, the largest brigade in the army, drove back the Iron Brigade in some of the fiercest fighting of the war. The Iron Brigade was pushed out of the woods, made three temporary stands in the open ground to the east, but then had to fall back toward the Lutheran Theological Seminary. Gen. Meredith was downed with a head wound, made all the worse when his horse fell on him. To the left of the Iron Brigade was the brigade of Col. Chapman Biddle, defending open ground on McPherson Ridge, but they were outflanked and decimated. To the right, Stone's Bucktails, facing both west and north along the Chambersburg Pike, were attacked by both Brockenbrough and Daniel.^[32]

Casualties were severe that afternoon. The 26th North Carolina (the largest regiment of the army with 839 men) lost heavily, leaving the first day's fight with around 212 men. Their commander, Colonel Henry K. Burgwyn, was fatally wounded by a bullet through his chest. By the end of the three-day battle, they had about 152 men standing, the highest casualty percentage for one battle of any regiment, North or South.^[33] One of the Union regiments, the 24th Michigan, lost 399 of 496.^[34] It had nine color bearers shot down, and its commander, Col. Henry A. Morrow, was wounded in the head and captured. The 151st Pennsylvania of Biddle's brigade lost 337 of 467.^[35]

The highest ranking casualty of this engagement was Gen. Heth, who was struck by a bullet in the head. He was apparently saved because he had stuffed wads of paper into a new hat, which was otherwise too large for his head.^[36] But there were two consequences to this glancing blow. Heth was unconscious for over 24 hours and had no further command involvement in the three-day battle. He was also unable to urge Pender's division to move forward and supplement his struggling assault. Pender was oddly passive during this phase of the battle; the typically more aggressive tendencies of a young general in Lee's army would have seen him move forward on his own accord. Hill shared the blame for failing to order him forward as well, but he claimed illness. History cannot know Pender's motivations; he was mortally wounded the next day and left no report.^[37]