And John, who is acting Head Coach with Dale McIntosh following the departure of Phil Davies, insisted there was much to play for in the remaining weeks of the season.
"It is easy to say we have nothing to play for; that is a problem if you feel that way," he said.
"We have got five games left and we are a well-supported club so we owe the supporters something. The players owe themselves something and the rest of the squad.
"When you put a jersey on you should give it everything you have got. We have got five games to go to restore some pride in the jersey.
"If you are a rugby player you go out on the field, no matter who you are playing for, and my mentality is you give everything you have got, irrespective of who you are, where you are, who against. You have got to have pride in what you do.
"I am still up for the challenge. If you are not then there is no point taking the job," he added.
"Both Dale (McIntosh) and I won't hide away from things. We didn't perform very well and the first place we look is at us.
"If everyone looks at themselves and how they perform, as a player, as an individual, as coach, then it will be a better place.
"You can't blame anyone else for it. The first place you look is the way you prepared. If we all do that, become accountable, then that is a positive. It is an uphill task but we can't shy away from the fact we have got to give it our best shot and that wasn't our best shot."
A hat-trick of tries from home winger Aisea Natoga and further scores from Ashley beck and Rhys Webb condemned Blues to defeat and John admitted the writing was on the wall after a poor opening 20 minutes.
"We are massively disappointed - that is an understatement," he added. "We sat watching the game and couldn't believe the first 20 minutes. We lost it there, every time we had the ball we gave possession away, didn't do the right things.
"There are boys disappointed and hurting in the dressing room. We have got to work harder and get a performance next week.
"We looked like we are lacking confidence and that is how we played that first 20 minutes.
"We struggled to maintain possession and have cool heads. You do that against a quality side then you come off second best and that is what happened.
"We showed some heart in the second half at times, we scrambled well and did some attacking. But the game had gone and it was a frustrating night."
John did, however, report more positive news of wing Harry Robinson who was carried off in the closing minutes in Swansea with an ankle injury.
He added: "We are hopeful over Harry. It looks like it might just be a soft tissue injury and it looked a lot worse than we hope it is.
"He is back with the players now and on crutches and in a protective boot, to give it stability, but we are hopeful it is not as bad as we first feared."