Widnes boss Denis Betts criticised his side for not being strong enough and lacking discipline after seeing them squander an 18-point lead before losing 34-24 to Castleford.
Widnes looked to be cruising at the Select Security Stadium after scoring three unanswered tries in the opening 20 minutes through Patrick Ah Van, Macgraff Leuluai and Corey Thompson.
However, Castleford staged a stunning fightback and, with Denny Solomona leading the way with a hat-trick, they managed to claim the spoils and leave Widnes coach Betts far from impressed.
He said "After the first five or 10 minutes we just went a little bit soft on ourselves.
"We were 12-0 up but I was still seeing things in us that weren't strong.
"There was a bit of ill-discipline and areas of our game where we gave them field-position too easily.
"They had nothing to lose and they came back. It was a massively disappointing day.
"We get 18 points up and Joe Mellor gets away down the sideline but effectively bombs a try.
"Defensively we were slack from the start. We just didn't control the ruck right through to the end of their sets."
In contrast to Betts, Castleford head coach Daryl Powell was understandably delighted with his side's performance and revealed the Tigers players were "buzzing" at the break as they sensed the chance of a dramatic comeback.
He said: "I don't think we kicked the ball for half-an-hour and you know you're going to be in trouble if that happens.
"Widnes were playing pretty sharp and putting us under pressure and we just needed to get a foothold in the game really and complete some sets.
"I've rarely seen a changing room as buzzing at half-time with the players just talking about the game.
"They felt they had every chance of winning it, you could just sense it.
"We just needed to tidy our game up but at 18-0 it looked quite difficult to do."
Ryan Boyle, Luke Gale and Paul McShane went over for second-half tries for Casteford, with Gale slotting over five conversions.
Powell added: " There's an immense amount of character in the team and the response today to being 18-0 down showed great determination to come out the other side when you're in a tough patch.
"Luke Gale's execution near the line got us opportunities and we were good enough to take them.
"Denny Solomona's finishing was again top quality and Jake Webster gave him some good opportunities with skill as well."