Grant ordered Hancock to cross the Po River and attack the Confederates' left flank, driving them back toward Burnside's position near the Ni River, while the rest of his command, in the center, watched for an opening to attack there as well. Hancock's II Corps advanced across the Po, but he delayed his attack until the morning. This error was fatal to Grant's plan. That night, Lee moved two divisions of Jubal Early's corps from Spotsylvania Court House into position against Hancock. On the morning of May 10, Grant ordered Hancock to withdraw north of the Po, leaving a single division in place to occupy the Confederates in that sector, while the rest of his army was to attack at 5 p.m. across the entire Confederate line. At 2 p.m., Jubal Early decided to attack the division, which retreated across the Po without being captured, destroying the bridges behind them.