NIGEL Clough was fuming with the match officials after Derby County's draw against Sheffield United at Bramall Lane.

Derby led 1-0 in the closing minutes when referee Graham Salisbury failed to see Clough's attempts to send on substitute Russell Anderson to help keep United at bay.

As Anderson waited on the touchline, Lee Williamson drilled in a stoppage-time equaliser for the home team to make it 1-1 and leave Clough far from impressed.

"The ball went out of play on the far side. I believe the officials are all microphoned up these days with expensive systems but the referee said he could not hear that we were trying to make a change. It seems a pretty lame excuse," said the Rams manager.

"The two linesmen, could they hear? Could they have alerted him?

"We might still have conceded, we don't know, but when the ball is out of play for that length of time you would think one of them between the four of them could have attracted sufficient attention to make the substitution.

"We were ready and waiting but we seemed to wait an age.

"It might not have made a difference – but it might have done."

Clough felt there was a lesson to be learned by his team in the build up to the goal.

Paul Green had possession deep in United's half but lost the ball.

"You have to be a bit more professional in those situations – win a throw-in or something – and then we will make the substitution when it is our throw," said Clough. "Just little things like that can make the difference."