Prescott passed away in the early hours of Saturday following a long battle with a rare form of abdominal cancer, and a minutes silence was held before the final group game at the KC Stadium in Hull.
McNamara recalled when Prescott presented his England side with their shirts before the mid-season international against the Exiles earlier this year, and spoke of the close affinity his squad had with the former St Helens and Hull full-back.
McNamara said: “We’re all shocked. Nigel (Wood) called me this morning to inform me and I was pretty upset by it.
“A lot of the players were attached to Steve. He came to present the jerseys against the Exiles, and he wasn’t in great shape then, but he dragged himself there, and did a speech with the players that still rings true.
“He said the body will do what the mind tells it to, and for someone who had just months to live to do what he did over six years is pretty superhuman. It was a strong message to myself and the rest of the group, and we all have a close affinity to Steve.
“Steve was a really close friend and someone we all admire. We all talk about him as a person, we talk about the feats he has achieved since being diagnosed, but we should also remember him as a fantastic rugby league player.
“You put his qualities as a player and a human being together, and it’s a sad loss for everyone who knows him.”
The sombre introduction to the match was reflected in the play, as it took 35 minutes for a try to be scored.