It was labelled as a publicity stunt by a club approaching crisis point. Five weeks on and the return of Neil Lennon to Parkhead in a first-team coaching role looks like an increasingly astute move by Gordon Strachan, the Celtic manager.

The club's remarkable resurgence in the last month has coincided with the Northern Irishman's return to the place where he won five championships in seven years as a player.

His first game in the dugout was Celtic's 1-0 defeat by Motherwell at home at the start of April, a result that appeared to extinguish their hopes of retaining the title. Lennon was inconspicuous that afternoon, leaning against the dugout and only occasionally making a point to the players or Strachan. Now he is a much more visible presence, barking instructions to the team and engaging in lively discussion with the rest of the coaching staff.

"He has already picked up a lot from being the captain and is very vocal," reflected Mark Wilson, the Celtic defender. "He sees a lot of what goes on . . . it is hard for him to stay quiet. He is over chatting with the manager if he sees things and it is a good sign he has the confidence to do that right away."

The qualities by which Celtic have hauled themselves back into the title race have Lennon stamped all over them. The midfield balance that Celtic had lacked since his departure at the end of last season has been successfully restored with the pairing of Paul Hartley and Barry Robson in central positions, a tactical move which happened when Lennon returned. Both have brought a steely pragmatism to the core of the team.

In the two recent Old Firm victories, in particular, Celtic won the physical battle. Both performances embodied the bullishness that Lennon brought to the cause during his seven years.

His mentality has also been brought to bear on other members of the team. Shunsuke Nakamura spoke warmly of Lennon's impact at the weekend. "He Lennon points out small things, especially about the midfield," said the Japanese playmaker, "and I think in the last month we have tidied up a few things. He may be a coach now but we just don't have his type of player in the team any more. He gets his passion about football across. He tells me something before every game."

In the modern game, the emphasis on tactics, training and preparation time is paramount, aspects that Strachan is strong on. Lennon's influence has been felt at a more basic level. Nakamura revealed that, with a few well-chosen words, his former team-mate inspired him to reach new heights. "Before the Rangers game the 2-1 win on April 16 he grabbed me and said, It is your day, you are going to be the hero today, we need you.' "So he gave me special powers," said Nakamura, who responded by scoring a magnificent opening goal and winning a second-half penalty for Celtic. "I hadn't really thought about it before but I think now he could be a good manager of this club in the future."

Nakamura, not a player to throw around compliments for the sake of it, is not the only one to have spoken of the difference Lennon has made. The Celtic first team have been lining up to praise his contributions. It is not lip-service. There is a genuine warmth when the subject turns to Lennon during press conferences. A dressing room in which you could have heard a pin drop four weeks ago has been reignited by his passion and personality.

The 36-year-old's outspoken style brought him into conflict with team-mates and referees as a player. He admitted on his return to Celtic that he would have to exercise more restraint as a coach. "When you are playing everything is instinctive, but I think now I will have to be more careful about how I go about it, and the manager will do most of it if there is a rollicking to be given out," Lennon said.

The signs are that Lennon has slipped seamlessly into his new role as an authority figure. "He gets the boys up and obviously he's not long out of the game so he knows what it's like to play in an Old Firm match," said Scott McDonald after the last derby match. "He was just being himself before the game - loud as he is, it's good. He's a great character and I'm sure he'll be here for years."

Lennon spent the last few years of his playing career preparing for a move into the dugout. He undertook his coaching badges at Largs, where his natural abilities stood out. He has already completed his B coaching badge at Largs, and will take his A licence in the summer.

"I found Neil to be excellent in many ways," said Jim Fleeting, the SFA's director of football development.

"Our courses can be quite demanding and he was busy at the time with Celtic, but he showed a great enthusiasm.

It became obvious that his coaching was of a high enough quality that the young players reacted to him. At that level he certainly had a natural talent."