He was playing for the Kia Toa club and represented Horowhenua in 4 matches against Manawatu, Foxton, Hawke's Bay, and Wellington B.
Cook then played for the combined Manawatu-Horowhenua team against New Zealand Māori which they lost 15–6, and Wellington.
His form was good enough to gain selection for Wellington in their match with Marlborough on June 22 where he scored 2 tries.
[8] He made a further representative appearances for Wellington against North Island Country on 9 August at Athletic Park.
[9] He then played against New Zealand Māori on August 12 where he scored a long range try after "Cook dashed in, and gathering the oval, was in an instant making full speed ahead for the goal line.
Then Poananga chimed in, but the St James three-quarter never faltered a moment, and finally scored a brilliant try near the corner".
His form for Wellington was good enough to gain selection for the New Zealand side to play the same opponents.
He was involved in a couple of near try scoring opportunities but New Zealand ultimately lost 18–10 in front of 20,000 spectators at the Auckland Domain.
[14] It was reported that Cook was to join the Ponsonby United side however he eventually ended up playing for Newton Rangers in the Auckland Rugby League competition.
He was selected for the Auckland side to play against Waikato Country on June 28 and scored a try in a 10–8 win.
He was somewhat 'injury prone' while at war and was admitted to the Second London General Hospital on January 14, 1918, suffering from a compound fracture of his left index finger.
Cook married Mary Lily Ryan 2 days before enlisting in the army for World War 1.