Tigers made it two wins from two in Betfred Super League despite being without eight senior players, including five who had featured in the round one victory against Toronto Wolfpack five days earlier.
“It was a pretty important win for us and a significant one looking at the team we had out there,” Powell reflected.
“All the values we place so highly were out there in massive amounts. The team was outstanding.”
The win came in Tigers captain Michael Shenton’s 300th Super League game and PowelI described his performance as “excellent”.
He said: “I asked the leaders to really step up and every single one of them did.
“The senior players were fantastic.”
Though Castleford were 20/1 outsiders to finish top of the table before the season began, Powell insisted their 100 per cent start isn’t a surprise.
“There’s a lot of doom-mongers about,” he said.
“I don’t know what’s wrong with them. I think we have had a great pre-season and even though we’ve got injuries, I know the work the players have done.
“They have worked hard and they are in a great place.”
Another boost was Junior Moors’ comeback from an injury suffered last season.
“It has been tough for him,” Powell admitted.
“He had a really bad injury last year with his hip and he needed an injection to play.
“It was good to see him out there.”
It was also a memorable debut for 17-year-old forward Sam Hall who was among Castleford’s substitutes.
Powell said: “His parents presented him with his shirt before the game, which was great.
“A young fella never wants his parents in the changing room, but emotionally I think it’s a really good thing to do.
“He is going to be a really good player in the future. His debut has probably come a bit earlier than anticipated, but he handled it really well.”
Tigers finished the game without stand-off Jake Trueman who was taken off in the second half, but Powell said he will be fit for next Saturday’s game at Catalans Dragons.
He explained: “He gets bad migraines which are exercise-induced.
“He gets them about five times a year, it was really bad and he was struggling to see. It’s not something that will keep him out for the next game.”
Tyler Hepi, Adam Milner and George Griffin are also set to return after missing the win over Wigan due to concussion and long-term casualty Mike McMeeken will “potentially” come into contention, Powell confirmed.