The former Hull KR prop signed for Tigers on a two-year deal earlier this month and - after playing more than 100 games for the Robins - said he is “really excited” about the move.
“I have been at Hull KR for seven seasons and I was ready for a change,” he confirmed.
“I can’t wait to get going and meet all the boys and Radders [coach Lee Radford] as well.”
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It is a new era for Tigers with Radford taking over the helm from Daryl Powell, who had been in charge since 2013.
Several key players have also left the club, but Lawler stressed: “They have brought in some good players and Lee Radford as well.
“I’ve spoken to a couple of the boys who’ve played under him and they’ve got nothing but praise for him.
“I am always looking to better myself and for new challenges.
“I’ve taken myself out of my comfort zone and I am really looking forward to it.”
Pre-season begins in the middle of next month and Lawler added “I’ll have a couple of weeks off and then get straight back into it.
“It is a really good squad, I can’t wait to get going and start training with all the lads.”
At 26, Lawler is one of the old heads in a young Knights squad for this evening’s game, which is a testimonial for Tigers’ Jordan Turner.
“I was buzzing,” he said of his call up.
“It is always a proud moment to get called up for your country, whether it’s Knights or seniors.
“I am looking forward to Friday and it’ll be nice to play at Castleford and get a feel of it and get ready for next year.”
Jamaica’s squad includes only three current Betfred Super League players, but Lawler insisted: “That doesn’t matter.”
He said: “They are playing for their country and you always step it up when you do that.
“We are expecting a tough game, but I think we are all up for it and we have been training well.”
That included a session against members of the full England squad on Tuesday.
Lawler said: “It was good to get chance to train with the senior squad and see how they go, their ethos and how they work.
“And to go against them, it was good to see how far we have come.”
Jamaica: from Johnson (Batley Bulldogs), Turner (Castleford Tigers), Magrin, Tomlinson, (both Dewsbury Rams), Bravo, Peltier, (Doncaster), Woodburn-Hall (Halifax Panthers) Golding, Lawrence (both Huddersfield Giants), Andrade, Coleman (Hunslet), Agoro, (Keighley Cougars), Ogden (London Broncos) McDonald, (London Skolars), I Farrell, J Farrell (both Sheffield Eagles), Brown (Workington Town), Jones-Bishop (York City Knights), Ball, Williams (both unattached)
England Knights: from Ashton (Warrington Wolves), Broadbent (Leeds Rhinos), Dodd (St Helens), Edwards (Leeds), English (Huddersfield Giants), Gannon (Leeds), Halsall (Wigan Warriors), Holroyd (Leeds), Lawler (Hull KR), Lees (St Helens), Lewis (Hull KR), Longstaff (Warrington), James McDonnell, Liam Marshall, Kai Pearce-Paul (all Wigan), Will Pryce (Huddersfield), Aaron Smith (St Helens), Walker (Warrington), Wilson (Huddersfield), Wrench (Warrington).
Kick-off: Friday, 7.45pm, at the Jungle.