As part of the third stage of General Sir Herbert Plumer's Passchendaele offensive, an attack against Broodseinde was scheduled for 4 October 1917. The 3rd Australian Division's 10th Australian Infantry Brigade was one of the assault formations charged with delivering the main blow, and ultimately with seizing the heavily defended Broodseinde Ridge. To provide defence against low-flying German aircraft during the attack, a group of 24 men, including Peeler, from the 3rd Pioneer Battalion's machine gun section were attached to the 10th Brigade's 37th Battalion.
The attack on Broodseinde began at 06:00 under the cover of an artillery barrage. Armed with a Lewis Gun, Peeler advanced with the initial wave. The Australians rapidly crossed the first 100 metres (110 yd) before becoming pinned down by a party of nine German soldiers, who were situated in a shellhole and sniping at the advancing troops. Firing his machine gun from the hip, Peeler dashed forward across the exposed ground and shot the group of Germans, "clearing the way for the advance". He performed similar feats on two subsequent occasions, killing several German soldiers and emerging unscathed.
The Australian force continued to press their assault, encountering pillboxes and machine gun positions as they pushed forward. One such machine gun position, situated in the open, held up the advance. Firing a single burst from his Lewis Gun, Peeler killed the gunner and caused the remainder of the gun's defenders to seek cover in a nearby dugout. One of the Australians then lobbed a "well aimed" grenade into the dugout, driving out ten soldiers whom Peeler then shot. Described as being "particularly prominent in the advance" by historian Charles Bean, Peeler "almost single-handedly" destroyed four German posts in an hour, accounting for more than 30 soldiers.
By 07:15 the following morning, the 37th Battalion had captured its objective, having seized eight pillboxes, several concrete dugouts, 20 machine guns and 420 prisoners. Two hours later, the Australians were in possession of Broodseinde Ridge. For his actions during the battle, Peeler was awarded the Victoria Cross; one of two Australians to be so decorated that day. On 12 October, eight days after Peeler's actions, the men of the 10th Brigade returned to the front line in an effort to exploit the success of the previous week. The ground in front of their position was dominated by a series of German pillboxes and had been turned into a quagmire by heavy rain. The brigade's attack was soon subject to a "torrent of machine gun fire", and Peeler was severely wounded in his right arm. Initially evacuated to the 11th Australian Field Ambulance casualty station, it was decided that his wound necessitated treatment in England so he embarked for the Northampton War Hospital on 15 October, arriving the following day.