Rotherham United: Millers duo heading to London to get lowdown on injuries

Defender Robertson and midfield man Crooks have both been playing through the pain in their joints.

They will visit a doctor in the capital to try and get some answers ahead of Monday's FA Cup trip to Solihull Moors.

Of Robertson, who has already missed several weeks of action with the problem, boss Paul Warne said: “We pulled him out and rested him for two or three weeks and he is still struggling and in pain.

“He is trooping on, but you can see he is still in pain.

"In the last 15 minutes at Portsmouth I even told him not to go up at the end because he couldn't get back in, which is sad.

“He is seeing a specialist in London, him and Crooksy are both going so hopefully we can get some news to help him with pain management and help him through.”

There are other injury concerns for Warne, who is waiting for news on Billy Jones' hamstring injury.

Jones suffered the problem in the final stages of the 3-2 loss to Portsmouth which saw the Millers finish the game with 10 men.

Jones was set for a scan on Thursday when the full extent of the injury – and any length of absence – will be determined, but Warne has ruled him both out of the cup game.

Warne added: “What is for sure is that unless there is a miracle he won't be available for the game on Monday which does leave us a bit weak at the back with Woody, Mattock and Billy out.”

Joe Mattock will also miss that match as his back problem is still ongoing.

“Joe Mattock is supposedly joining in training next week, but because of the injury he has got with his back and a certain movement I don't want to count my chickens,” Warne added.

“I hope he comes back because we have missed him. Hopefully he joins back in next week and he will be available for the Rochdale game.”

The Millers travel to Damson Park on Monday night for a TV clash against the non-league side on BT Sport, which comes after any potential third-round opponent will be known.