[152] One Union line held the Confederate attack off for several hours at a place later called the "Hornet's Nest", giving Grant time to assemble artillery and 20,000 troops near Pittsburg Landing.[153] The Confederates finally broke through the Hornet's Nest to capture a Union division, but "Grant's Last Line" held the landing, while the exhausted Confederates, lacking reinforcements, halted their advance.[154] The day's fighting had been costly, with thousands of casualties. That evening, heavy rain set in. Sherman found Grant standing alone under a tree in the rain. "Well, Grant, we've had the devil's own day of it, haven't we?"Sherman said. "Yes," replied Grant. "Lick 'em tomorrow, though."[155]
Bolstered by 18,000 fresh troops from the divisions of Major Generals Buell and Lew Wallace, Grant counterattacked at dawn the next day and regained the field, forcing the disorganized and demoralized rebels to retreat back to Corinth.[156] Halleck ordered Grant not to advance more than one day's march from Pittsburg Landing, stopping the pursuit of the Confederate Army.[157] Although Grant had won the battle the situation was little changed, with the Union in possession of Pittsburg Landing and the Confederates once again holed up in Corinth.