all RVNAF aerial observation and air support. As the rain increased, so did the PAVN bombardment, 1600 rounds falling in one hour, and the battlefield was obscured in smoke. ARVN infantry could hear the approach of tanks. One column of T-54s came out of the rubber plantation and forest to the north, and another line of six advanced from the south. The three ARVN M48s withdrew, and at 18:00, nearly caught in a double envelopment, the 8th Infantry fell back, first about 300 meters where they attempted to establish a new line, then 300 meters farther back where the troops of the 8th rallied and held on the western slope of Hill 25. With victory seemingly so close, General Thuần was deeply disappointed by the rout of the 8th Regiment, and his disappointment changed to anger when he learned of the relatively light casualties suffered by the 8th: 6 killed, 29 missing, and 67 wounded. But even if the 8th Infantry leaders on the scene could have held their troops in their exposed positions in front of Base 82, the regiment probably could not have survived the PAVN counterattack. In any case, General Thuần ordered an immediate investigation of the circumstances of the 8th Infantry's failure and subsequently dismissed the regimental commander. On 11 September, the 8th Infantry was replaced by the 9th, and all three battalions of the 9th Infantry moved into position on the west slope of Hill 25. Combat losses since the start of the PAVN offensive in May, combined with the slow flow of the replacements into the regiment, had reduced battalion strength to under 300. Between 12 and 18 September, the 9th concentrated on reconnaissance, planning, and improvement of positions. As the 9th Regiment prepared for the attack, the PAVN was beginning to execute another relief in the Bến Cát battlefield. The 141st Regiment made preparations to leave the Base 82 area and turn over its defense once again to the 95C Regiment. With the 2nd Armored Cavalry Squadron protecting the right (north) flank, and two Ranger battalions protecting the left, the 9th Infantry Regiment began its attack toward Base 82. The two attacking battalions, the 3rd Battalion on the right, north of Route 7, and the 2nd on the left, crossed the line of departure on Hill 25 on 19 September. Moving slowly, with excellent reconnaissance and effective artillery support, the ARVN methodically eliminated,