Sammy Lee’s future as Bolton Wanderers manager appeared increasingly bleak last night in the face of a revolt among his senior players. His position had been weakened by a rift with Gary Speed, who resigned from his coaching role at the club yesterday, but it emerged last night that unrest throughout the squad is at such a level that it threatens to end his tenure at the Reebok Stadium after only five months.

The Bolton board had been prepared to give Lee until the end of the month to save his job, with particular importance placed on the home match against Aston Villa on October 28, but after the events of this week, culminating in Speed’s resignation, the club’s hierarchy believes that Lee’s situation is becoming untenable.

With difficulties growing on the pitch, after only one win in their opening nine Barclays Premier League matches, and on the training ground, the board is considering potential candidates to replace Lee, including Paul Jewell, who has been out of work since leaving Wigan Athletic last May, and Adrian Boothroyd, the Watford manager.

The Times revealed on Wednesday that Speed was preparing to step down from his coaching duties because of irreconcilable differences with Lee, who appointed him as player-coach when he took over as manager in May. Lee claimed that he “relieved him [Speed] of his coaching duties because I want him to focus on his game”, but Speed insisted that it was his decision because “it wasn’t working out”.

Speed’s supposed demotion could be perceived to strengthen Lee’s position, but Phil Gartside, the chairman, and Eddie Davis, the owner, fear the opposite. Morale among the Bolton players has been low since they returned for preseason training in July, with Speed, Iván Campo and Kevin Nolan, the captain, among those who have expressed unhappiness with the manager and his methods. According to dressing-room sources, the discontent is spiralling out of control, with most of the players believing that a change of manager is required if the club are to recapture the success that they had under Sam Allardyce.

Lee spent two seasons working as assistant manager to Allardyce, which made him the perfect candidate to succeed him in the view of the board, but his desperation to make a clean break from the previous regime has alienated players and staff. Several sources claim that Lee’s obsession with asserting his authority has reached absurd levels. Even the conference room at the training ground, which was known as the “war room” during Allardyce’s seven years in charge, has been renamed as the “bunker”.

Lee believes that he has been victimised by a subversive element within the club. “It’s bitterly disappointing that these things are leaking out,” he said. “People are trying to undermine what we are trying to do. I hear things about my methods, but I’ve been with these lads over two years.” It is not only among the players, though, that Lee has caused unrest. Several members of his coaching staff have left Bolton in recent weeks, while at least three others, including some who were brought to the club by Lee over the summer, have spent the past week considering their futures. Players and staff are united in dismay at Lee’s treatment of Ricky Sbragia, the former Manchester United coach, who was marginalised to an alarming degree in the opening weeks of the campaign before being reinstalled as first-team coach, largely on the insistence of the players.

The situation appears dismal for Lee, but yesterday he called for unity. “It’s important that all of us focus on what we are trying to do,” he said.