Rafa Benitez's simple message to his players ahead of Birmingham's visit to Newcastle

Jonjo Shelvey and Paul Dummett were controversially sent off in Friday night’s 2-1 defeat to Nottingham Forest.

The home side came from behind to beat Benitez’s nine-man side, who were left fuming at the antics of Henri Lansbury and the officiating of referee Stephen Martin.

Forest midfielder Lansbury was involved in the separate incidents which saw Shelvey and Dummett dismissed.

It was a third successive loss for Championship leaders Newcastle, who also went out of the EFL Cup at the quarter-final stage last week.

United’s lead at the top of the division has been cut to one point ahead of Saturday’s home game against Birmingham City.

“We know that we made some mistakes,” said Newcastle manager Benitez.

“You cannot change things now.

“You have to concentrate on what you have done well and the mistakes you have made and then try to think about the future. It’s a long race, and we have to carry on.”

Benitez was proud of how his players reacted to losing two players.

Newcastle played the entire second half with nine men – and came within minutes of taking a point.

Forest’s winning goal came in the 86th minute.

“I think we did really well if you consider the first goal (scored by Nicklas Bendtner) was offside,” Benitez told BBC Radio Newcastle.

“After, we had some chances. We just tried to defend and play counter-attack, but it’s quite difficult.

“(With) every decision against you, it’s not easy.”

Meanwhile, Benitez and his staff will this week assess Jack Colback, who has been sidelined with a vision problem. The midfielder – who suffered a gash above his eye after taking a blow to the head in October’s 6-0 EFL Cup home win over Preston North East – hasn’t featured since last month’s 2-0 win over Leeds United.

Benitez hopes Colback, left out of his last two squads as a precaution, will soon be available.