In a fairly-even contest between the two sides, a late four-pointer to Roosters fullback Michael Gordon secured the win for the visitors, but Griffin said his men were out of luck after a number of 50-50 calls failed to go their way and a strong defensive effort was trumped by the Tri-colours.
"Obviously we got beat with points on the scoreboard but I thought it was a really good effort and something we can build on," Griffin said post-game.
"I thought we were very unlucky but that's what happens at this level.
"They [Roosters] had 58 per cent time in possession so I feel sorry for the players they didn't get to feel that tonight but we'll build on that and feel it another time.
"To win games in this competition you need to be a good defensive team and we almost pulled off a win tonight without the ball. We got a couple of things technically wrong on that right side but apart from that, I thought we were brilliant in defence.
"I thought tonight was better than last week and last week was better the first week."
Despite having 20-less carries compared to their opposition, the Panthers matched the Roosters in the forwards with Trent Merrin, James Tamou and Reagan Cambell-Gillard all contributing with high numbers up front.
"I thought our forward pack was outstanding and both really went at each other all night," Griffin said.
"He hasn't played a lot of footy, Trent [Merrin]. He didn't get much work in the first game [against the Dragons] as we were standing behind the goal posts most of that day and then last week he got about 50 minutes.
"He played 73 minutes in the middle [tonight]… that will do him the world of good, it was a blowout for him.
Griffin also confirmed James Fisher-Harris will spend at least the next fortnight on the sidelines after fracturing his cheekbone early in the first half of the two-point loss.
"He's got a fractured cheekbone unfortunately… he had a head clash early on in the game and as soon as he tried to blow his nose it just popped out.
"He'll be a few weeks out.
"We've obviously got some areas to work on but I thought even though we had to overcome James' injury, we did a good job to hold the game together.
"As a club we were very courageous and a few things went against us tonight as everyone seen."
