USA coach Terry Matterson was thoroughly impressed by the togetherness shown by his side during their 32-20 win over the Cook Islands on Wednesday.

Mark Offerdahl and Craig Priestly scored tries in the final 10 minutes as Matterson's Tomahawks came from behind to win their opening game in the 2013 Rugby League World Cup.

"That was nothing less than these guys deserved," Matterson told reporters. "They have come together, they did not know each well at all and they went through some adversity.

"But we had a good trial win in France and we have had a great time together and I am so proud of these guys.

"To do that after such a short preparation, and to come from behind a couple of times, once because of a real tough decision on one of their tries, means I am over the moon."

Matterson only took charge of the USA earlier this month, following the resignation of Brian Smith.