He practically singlehandedly protected the left flank of his company's position in the offensive to break the Germans's Gothic line. Company B was the extreme left assault unit of the corps. The advance was stopped by heavy fire from Monticelli Ridge, and the company took cover behind an embankment. Sgt. Johnson, a mortar gunner, having expended his ammunition, assumed the duties of a rifleman. As leader of a squad of seven men he was ordered to establish a combat post 50 yards to the left of the company to cover its exposed flank. Repeated enemy counterattacks, supported by artillery, mortar, and machine-gun fire from the high ground to his front, had by the afternoon of 16 September killed or wounded all his men. Collecting weapons and ammunition from his fallen comrades, in the face of hostile fire, he held his exposed position and inflicted heavy casualties upon the enemy, who several times came close enough to throw hand grenades. On the night of 16-17 September, the enemy launched his heaviest attack on Company B, putting his greatest pressure against the lone defender of the left flank. In spite of mortar fire which crashed about him and machine-gun bullets which whipped the crest of his shallow trench, Sgt. Johnson stood erect and repulsed the attack with grenades and small-arms fire. He remained awake and on the alert throughout the night, frustrating all attempts at infiltration. On 17 September, 25 German soldiers surrendered to him. Two men, sent to reinforce him that afternoon, were caught in a devastating mortar and artillery barrage. With no thought of his own safety, Sgt. Johnson rushed to the shell hole where they lay half buried and seriously wounded, covered their position by his fire, and assisted a medical corpsman in rendering aid. That night he secured their removal to the rear and remained on watch until his company was relieved. Five companies of a German parachute regiment had been repeatedly committed to the attack on Company B without success. Twenty dead Germans were found in front of his position. By his heroic stand and utter disregard for personal safety, Sgt. Johnson was in a large measure responsible for defeating the enemy's attempts to turn the exposed left flank.