Sheffield co-promoter Peter Mole admitted he was bitterly disappointed with a below-par performance at Newcastle on Sunday.
The Tigers left Brough Park with their Knockout Cup dreams in tatters after a crushing 62-28 loss, their heaviest of the season.
It leaves them in need of a massive recovery in the second leg at Owlerton this Thursday (7.30) to book their place in the semi-finals.
Mole conceded it was a night to forget for his team – but he also praised the ruthless Diamonds for their dominant display.
“It didn’t go to plan for us, and it’s difficult to say if we were poor or Newcastle were very good,” said Mole.
“It was probably a combination of both in the end. We were below par and it was a very disappointing performance, but Newcastle rode very well and showed how strong they are at home.
“Their three heat-leaders were always expected to be strong, but Ludvig Lindgren, Victor Palovaara and Lewis Rose all scored big points and they had race wins in every department.
“There were a few surprising refereeing decisions, but it was a bad night at the office for us and not the result we wanted from the first leg.
“Hopefully we can get our confidence back on Thursday with a win.
“We know we’ll need something special to get through, but it’s not over yet and we’ll be out to try and get a big win in the second leg.”