The squad got together for a training camp in Loughborough last weekend, in preparation for the match on June 14.
McNamara said: “The Origin game does form an important part of our preparations for the World Cup but more importantly it’s a fixture we very much want to win.
“We spoke at length about playing the Exiles during our camp at Loughborough last weekend and it was clear from all the players that there is a real hunger not just to feature in this match, but to win it.
“We won the first of the two Origin games last year but were pipped at the post in the second one: this year it’s a one-off game and an opportunity for all of us to put down a marker.”
Tickets for the International Origin Match at The Halliwell Jones Stadium, Warrington, on Friday June 14 cost from £20 (£15 for 65+ students, £10 for under-16s) and can be purchased by visiting www.rugbyleaguetickets.co.uk/