HUDDERSFIELD Giants coach Nathan Brown believes he has discovered the reason for his side’s alarming slump, just in time for a bid to reach Wembley.

The Giants go into Sunday’s Carnegie Challenge Cup semi-final against Warrington at the City of Salford Stadium on the back of their worst Super League run since Brown took charge four years ago.

Brown’s men have gone from the top of the table to seventh after losing seven of their last eight league games, culminating in a 52-6 thrashing by lowly Castleford last Sunday.

The Australian, who is leaving the Giants at the end of the season to join St Helens, accused his players of not trying and is confident he has found an explanation, which he is keeping to himself.

"We had a lot of people who didn’t try and weren’t committed at all the other day," he told a news conference at the Galpharm Stadium. "There is always an underlying factor for why that happens. Players don’t go out there deliberately to do that.

"We’ve based this club in my time here on trying to out-work and out-enthuse sides and we’ve done it with great effect a lot of times against teams with much more talented rosters.

"When you discover what that underlying factor is, you can move forward. It would appear that we’ve solved some issues."

Asked to elaborate about the underlying factor, Brown replied: "That’s none of your business, without being rude."

Brown described Sunday as his "worst day" since joining the Giants and admits he considered his position in the wake of the heavy defeat.

"When people don’t try, you’ve got to look at that because they don’t not try for no reason," he added. "There’s obvious issues.

"You’ve got to look at numbers of things. You don’t just blame players. That’s easy.

"Some coaches like to call the players all the names under the sun but, when people don’t put in a good effort, you’ve got to look and find out why they’re not putting the effort in and then you can move forward."

Brown is hoping winger Luke George, the club’s leading tryscorer this season, will pass a fitness test after being concussed at Castleford and confirmed that England prop Eorl Crabtree will return after being rested.

But Australian forward Luke O’Donnell will be absent with a mystery injury.

"Luke won’t play, unfortunately," said Brown, who declined to divulge the nature of the injury.

"He’s a bit of a loss for us. He’s obviously an important player.

"We’ve haven’t had him as much this year. The reality is we generally go better when we’ve got less big-name people playing, for whatever reason."

Despite his side’s dismal run, Brown insists there is no need to ring the changes.

"We’ve got a style of play and a group of players that for the first 14 or 15 weeks got us to the top of the competition and to a Challenge Cup semi-final," he said.