With two brigades of 2,500 Union cavalrymen bearing down upon them, the Confederate rear guard formed a skirmish line. This maneuver delayed Union troops long enough for the Confederates to establish a main line of defense 800 yards south. The two Confederate cavalry divisions numbered approximately 7,000. The field was wet and muddy from the previous night's rain, and hundreds of horses and wagons had trampled the ground. In spite of the precarious conditions, both sides quickly moved into position at 10:30 a.m. Confederate artillery opened fire first, followed by the Union. The Union cavalry charged but hesitated and stopped when the Confederates showed no sign of breaking. The second Union regiment then moved around the first, triggering a chain reaction as the entire Union line charged.