Mellor picked up an injury last week during the Tigers‘ loss at Toulouse Olympique and scans have now confirmed that the back-rower has a broken bone in his leg.

The good news is that the 31-year-old won’t need surgery, limiting the amount of time he could spend on the sidelines. However, the forward could still be set for a lay-off of around two months, ensuring he will be looking at a return to action in late April or early May.

Joe Stimson will pick up the captaincy duties in Mellor’s absence, but his loss is certainly a big one for Carr and Castleford.

“He picked up a broken leg in Toulouse, it’s a weight-bearing bone unfortunately and he’ll be on the sidelines for an extended period until we can get that healed,” Carr told the press on Thursday. “It’s the bone just under his knee on the outside.

“It doesn’t require surgery which is a positive but it is a weight-bearing bone, so we just need to take our time until that heals, which is unfortunate for him.

“Around eight weeks, we think. Being a bone, you can’t do much about it, you have to wait until it heals. Taaffe in round one and now Mellor in round two are a couple of key blows to our roster, both in their football ability but their leadership abilities and confidence they bring to the group. It is a blow but at the same time it’s next man up mentality.”

Castleford have been boosted by the return of Zac Cini, who will be fit enough to feature on Friday night against Huddersfield Giants, should he come through the final day of training unscathed.

However, Brock Greacen remains out through injury, despite featuring in last week’s 21-man squad.

“It’s not a setback but we thought it was coming along quicker than it was,” Carr said on Greacen. “He was pretty crooked through the week too with some illness and that put his rehab back because he wasn’t able to train. We’re really hopeful that he’ll be ready for the Leeds match on Sunday week.”

Carr will hope to have Semi Valemei at his disposal sooner rather than later, too, with the winger approaching the end of his recovery period after picking up a knock in pre-season.

“I have a date in my mind but I don’t want to pressure it,” Carr said when asked when Castleford Tigers fans might see the Fijian. “He was out there running on the field and that was the first time I’ve seen him on the field, which was a good thing to see but we’ve got to make sure we take the right steps so when he’s back, he’s back for good.”