On 24 July 1916, the battalion entered the Battle of Pozières. On 25 July, it was seeking to consolidate the Australian positions around Pozières. Cooke, operating a Lewis gun, was sent forward with his assistants to stabilise an unsafe section of the line. He and his companions secured the area but was exposed to long range machine-gun fire which soon accounted for all but Cooke. Even after running out of ammunition, he continued to man his post in the face of a German counterattack during which he was killed. The battalion was withdrawn from the front lines two days later, having incurred 347 casualties.
Cooke was recommended for the Victoria Cross (VC) for his actions of 25 July. At the time, the VC, instituted in 1856, was the highest gallantry award that could be bestowed on a soldier of the British Empire. The award of the VC to Cooke was gazetted on 9 September 1916 and the citation read as follows:
For most conspicuous bravery. After a Lewis gun had been disabled, he was ordered to take his gun and gun-team to a dangerous part of the line. Here he did fine work, but came under very heavy fire, with the result that finally he was the only man left. He still stuck to his post, and continued to fire his gun. When assistance was sent he was found dead beside his gun. He set a splendid example of determination and devotion to duty.