"They've both been really impressive and have thoroughly earned selection,'' he said.
"It's so exciting for them, their families and for us as a club to have them making their debuts in our first game of the season.''
In naming 20 players, McClennan said there were still some selection issues.
"We haven't quite settled on the final line-up yet. We have a few things to consider and we'll make a final decision closer to the time.''
Hurrell, a schoolboy rugby union star, was a sensation in his first season of rugby league last year, scoring 22 tries in 21 games for the Junior Warriors. He has also been a standout in his three trial appearances so far.
Henry has come through the club's development system and ended his NYC career with 64 games, the most by a Junior Warriors' player. A back rower, he underlined his ability by excelling in the centres during the trials.
Hooker Friend, who has played 135 NRL games, also impressed in his trial outings against his old Gold Coast side and South Sydney.
With front row candidates Jacob Lillyman, Sam Rapira and Steve Rapira all sidelined with injury, McClennan has named Sione Lousi and Ukuma Ta'ai to provide support for frontline props Russell Packer and Ben Matulino.
While Lillyman, Sam Rapira and Micheal Luck are missing, 12 of the club's 2011 grand final line-up remain in the 20-man squad named today.
Captain Simon Mannering, the club's Player of the Year in 2011, starts the season just four games short of simultaneously reaching his 150-game NRL milestone and also leading the team for the 50th time. He played all 28 of the club's matches last year, as did Matulino and Feleti Mateo.
Referees Tony Archer and Ben Cummins have been named to control Sunday's match.
Warriors: Kevin Locke, Bill Tupou, Konrad Hurrell, Jerome Ropati, Manu Vatuvei, James Maloney, Shaun Johnson, Russell Packer, Nathan Friend, Ben Matulino, Feleti Mateo, Simon Mannering (c), Elijah Taylor. Interchange: Lewis Brown, Sione Lousi, Ben Henry, Ukuma Ta'ai, Glen Fisiiahi, Krisnan Inu, Alehana Mara.
