'Celtic players need to restore the club's reputation and their own', says new boss Neil Lennon

• Neil Lennon with his assistant Johan Mjallby

The club's new interim manager was a horrified spectator as Celtic lost 4-0 to St Mirren, their heaviest non-Old Firm domestic defeat for 30 years prompting the dismissal of Mowbray on Thursday.

Lennon wasted no time yesterday in outlining his view of the performance to the players and expects an instant response when they face Kilmarnock at Celtic Park today in the first match under his charge.

"I have told them that Wednesday night was totally unacceptable," said Lennon. "I never want to see that again. I made it pretty clear what is expected of them between now and the end of the season. I want them to play from the gut. They have their professional pride to play for with ten games left. They need to restore the club's reputation and their own.

"I think there is a softness about us. I'd like to eradicate that. I think mentally we're not as strong as we should be. Rangers have shown over the course of the season that they are quite able to grind out results and we've not been able to do that, we've only done it sporadically. I think there should be more of a tempo to our play as well, more concerted pressure, which I don't think we have enough of.

"If the players are not up to it, then you have to change it and get someone else in. I want them to show a bit of character and I expect nothing less after Wednesday night. I think they have the character.

"The game against Kilmarnock could go one of two ways. It can either be a great day for the players or a difficult one. If the crowd do get anxious, then the players have to take it and show the character to come through it."

Lennon has enlisted the help of his former team-mate John Mjallby for the remaining six weeks of the season and believes the Swede can play a crucial role in trying to instil the kind of spirit and attitude which propelled Celtic to such success when both men played under Martin O'Neill's management at the club.

"Johan knows the way I think about the game," said Lennon. "I can trust him and have spoken to him regularly over the past year and a half on various aspects of the game. And he is also a really big guy, you know? He has a presence about him which I think is important. But we aren't just cheerleaders, we aren't ranters and ravers.

"He's an intelligent guy who captained his country at the World Cup and was a first-class player here. I think he might help brush up on our defensive frailties as well.

"I haven't spoken to Martin O'Neill since I got the job, but I think he will be pleased for me. I learned a hell of a lot from him and he basically moulded my career for me. It's maybe too simple to say that my team will play like Martin's team, but I would like them to have that sort of mentality. I want them to play with a bit of tempo, a bit of width and an attacking belief. Do I have the players to do that? I don't know, but we'll find out in the next few weeks."

Team captain Scott Brown has backed Lennon to become the new Celtic manager on a permanent basis.

"I think that would be great," he said. "He knows what it is all about. He loves the club. He was a leader on the park and it looks like he will be a leader as manager as well."

He added: "There is the Scottish Cup and that is what we are looking forward to now, that is our main aim.

"Hopefully if we do win it, it will get the fans behind us again and it will get Lenny a full-time job as well. I think that's what we are here for, to help him, and he is here to help us as well.

"The players respect Lenny and look up to him. He has been a leader at this club and captained them to the Uefa Cup final. There is a lot of pressure with fans, media and things like that and Lenny knows what it's about and will be the right man to deal with it."

Asked if Mowbray had got the players together yesterday to say farewell, Brown replied: "I wasn't here. I was at court."

But the player expressed his gratitude to the former manager yesterday.

"It was one of the proudest moments of my career when he made me captain," said Brown. "I had a good relationship with him, at Hibs and at Celtic, and it's not nice to see any manager go. I'll give him a few days then give him a call.

"I think the gaffer was doing not a bad job. He was enjoying it and the lads were enjoying it. But it's not us who make the decisions.

"Lenny has come in and we have to get on with it. But we have to take a lot (of responsibility] as well.

"We have let ourselves, the fans and the manager down but it's a fresh start and hopefully we don't do the same thing again."