Lewis Grabban set to miss 'a few weeks' but Sunderland unconvinced free agent is the solution

With Duncan Watmore and Josh Maja still recovering from injury, the Black Cats have been left short up front and while they are still waiting to discover the full extent of Grabban's injury, he is likely to miss most games in a busy month of fixtures.

Grayson said: "He's had a scan on his hamstring and with these injuries it is not going to be a few days, it is going to be a few weeks.

"We have to wait for the scan results to come back to find out the severity.

"But he will miss out this weekend and who knows after that – we'll have a better idea over the next 24 hours when the scan results come back," he added.

"It's not ideal because it is an area of the pitch where we are short of numbers at this moment in time, but you have to deal with these situations and players who come into the team have to come to the fore.

"Hopefully in the next week or ten days we will have more attacking players coming back into the team who will make us more effective and give us that extra quality that we need."

That injury has fueled further discussion of a potential free agent signing, with Sunderland already left a striker short before Grabban's injury.

Grayson, however, is unconvinced that is a viable option for the Black Cats and warned that any new recruit may take longer to reach fitness than Grabban anyway.

He said: "I’ve not really had a conversation with Martin about it. You’ve got to be careful because the ones out there have probably not trained for a while, they’re not up to the standards of what you want to be able to throw them in straight away.

"So it could take four to six weeks to get them there and before you know it you’ve got McGeady, Watmore, Grabban and Maja back. We might just have to ride out this difficult period when we’ve not got the bodies available. But I won’t dismiss it, its something to consider.

"You’d always want more, of course you would. In an ideal world we’d probably have another target man to compete with James Vaughan, I see Lewis more as a ten who floats around. He can play up front on his own, of course he can, but he’s maybe not an out and out number nine."

Grayson has also revealed that John O'Shea will miss the game with a calf problem, though Aiden McGeady and Lamine Kone could return to contention.

He said: "John had his calf problem from the Ireland camp, he missed the game with it and he’ll miss it tomorrow as well. I expect him to be available Wednesday night and certainly for Cardiff.

"I think on Tuesday night we looked defensively very solid, Forest hardly lay a glove on us. One mistake and we got punished.

"Both [Aiden & Lamine] will come out with us this morning and let’s just see where they go. They’ve both done a bit of work with the physios since Tuesday so we’ll just have to wait and see.

"Even the early part of this week Aiden did some work and you thought he might be available for Tuesday, he just felt a bit of stiffness and we have to be very careful, you’d rather he miss another game or so than run the risk of being out for four, six, eight weeks or something like that."