Rhinos were beaten 38-4 by Australian champions North Queensland Cowboys, completing a 3-0 whitewash for the NRL in the World Club Series.
Injury-hit Rhinos matched the Aussies in the first half and it was 4-4 at half-time, but there was no stopping the Cowboys in the second period when they ran in six unanswered tries.
It was Leeds’ second successive world title defeat and their fourth overall.
No Super League team has won the competition since Rhinos’ victory over Manly Sea Eagles in 2012.
Leeds dominated territory and possession early on, but managed just one try – through skipper Rob Burrow – against an outstanding defence.
Hardaker said: “I thought we were the better team in the first half.
“We were unlucky not to get more points on the board, but it doesn’t really matter what happens in the first half, it is what happens in the second that counts.”
Cowboys, who had the wind in their favour after half-time, scored within a minute of the resumption and Leeds never got back into the game.
“It was a bit of a soft try to concede,” Hardaker admitted.
“I’m not sure what the difference was in the second half, but they got a bit of a roll on. They were winning the rucks and winning the tackles and we could not recover.
“Within 10 minutes they scored two tries and heads go down after that.
“I try to pick people up as much as I can and encourage them to keep going, but they were just too good for us towards the back end.”
Hardaker said inquests into the defeat will be saved for later.
He added: “We haven’t really spoken about it yet. We were with them in the first half and we were unlucky not to go into the second half leading, but their second try did us and when they scored another try after that we were struggling.
“But we will benefit from being in this, without a shadow of a doubt. I have only played against Johnathan Thurston once and it is good to play against people like that.
“There’s plenty of positives to take out of it and we have to get up for the Catalans game [on Saturday] now.
“We’ve been given some tough fixtures, Widnes away before this and then a trip to Catalans after it, but we’ll be back in this week, we’ll take some positives out of this and we’ll be ready to go against Catalans.”
Rhinos were without seven players through injury last night.
To add to their woes, prop Mitch Garbutt was sent-off in the second half for striking.
A ban would rule him out of Saturday’s tough game in Perpignan.
Rhinos’ Australian prop Adam Cuthbertson said: “It is always tough losing, especially in a big game like this.
“We had a tough week with some players out, but we had a really good dig in the first half.
“Unfortunately North Queensland were too fast in the second half. We had a few good chances, but we turned the ball over on play one, two and three a few times.
“We could have had more points if our execution had been a bit better.”