won his 50th international cap
in last year's Four Nations final defeat against Australia, has only recently returned to competitive action following a long-term neck injury.
McNamara stressed that being left out of this squad did not necessarily represent the end of Morley's international career.
"There is no bigger advocate of Adrian than me," he said. "But he's just coming back from a bad injury and I believe there are players ahead of him in terms of form. Adrian I'm sure will come bouncing back.
"For the other players that have missed out, the door is still open and it is important they continue to work hard in the domestic competition with a view to getting back in the squad," he said.
"It is a pleasing situation to be in. We have competition for places right across the team and every player knows they have to perform week in, week out if they are going to be part of the England programme."
The 21-man squad features 10 players from last year's Four Nations campaign.
Brough, a former plumber who has captained Scotland but
opted for England
last year only to suffer an
ankle ligament injury
on the eve of the inaugural fixture with the Exiles, is one of four potential debutants.
Carl Ablett of Leeds, and Wigan's Josh Charnley and Lee Mossop are other players hoping for their first caps.
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