The Canterbury captain has been battling a shoulder issue since Good Friday and has frequently had to undergo painkilling to get on the field for the Bulldogs during a season of struggle.
The strike centre's form has been questioned and Crichton has also been on restricted training duties in the lead-up to Origin I in Sydney on Wednesday.
"The body's good and I'm very excited for this week, and the opportunity to represent NSW again," Crichton told reporters on Monday, while sporting heavy padding on his right shoulder.
"The body's probably the best it's felt. I got to rest up for a couple of days, which is good for the body and for the mind as well.
"But the last couple of training sessions I've been around the boys and the energy that the boys bring into camp has been good.
"Our preparation has been really good, and I can't fault the execution and the energy the boys have been bringing in for game one."
Crichton looms as the most likely option to fill in at fullback should anything happen to James Tedesco at Accor Stadium.
The 25-year-old Crichton played in all three games of last year's series, which the Blues lost 2-1 after claiming victory in the Brisbane series opener.
Crichton has conceded he was fortunate to earn NSW selection given the Dogs' form this season.
"There's always fire in my belly to prove those people wrong, but I know who my inner circle is and the people to listen to," Crichton said.
"There's always going to be doubters out there and there's always going to be people questioning my form.
"As long as I've got the confidence in myself and the confidence in that room in there from the boys is the main thing.
"You learn a lot about yourself when you're losing as well and a lot about the boys around you and your culture."
Crichton is expected to line up at left centre against rising Sydney Roosters star Rob Toia.
The Samoan international has mostly played on the right this year at club level but has made the switch to accommodate Brisbane tough nut Kotoni Staggs.
Broncos centre Staggs is playing just his second Origin game since his debut four years ago and Crichton predicted his centre partner would leave his mark.
"The way Kotoni runs and the aggression that he plays with, he's definitely built for the Origin arena," Crichton said.
"Seeing the way that he's gone about his business - not just on the field - but on day's off and getting his body and his mind right.
"I know that he's going to go out there firing and he's going to take his opportunity this time and he's going to be probably one of our best."
