Both Scurry and Slough decided to attack on March 28 and set out early to do so. Expecting the Confederates to remain in Apache Canyon, Slough sent Chivington with two infantry battalions, under Lewis and Wynkoop, out in a circling movement with orders to go hide out at Glorieta Pass and hit the Texans in the flank once Slough's main force had engaged their front. Chivington did as ordered and his men waited above the pass for Slough and the enemy to arrive. However, instead of remaining at Apache Canyon as Slough had expected, Scurry advanced down the canyon more rapidly than Slough had anticipated. Scurry believed the Union force was retreating to Fort Union. He intended to attack them until Green could arrive. One cannon and a small guard was left at Johnson's Ranch, while the rest of the Confederate force—more than 1000 men—marched eastwards along the Santa Fe Trail.