Hammers look to experienced Wolves defender to solve defensive injury crisis following FA Cup humiliation at Forest.
The 30-year-old has spent most of this season on loan at Sheffield Wednesday in the Championship, making 18 league appearances for the Yorkshire club, but will spend the rest of the campaign at Upton Park.
The Hammers have been up against it following a long-term injury to Winston Reid and the recent absences of James Collins and James Tomkins.
Tomkins is also facing a charge of assaulting a police officer, much to the anger of the increasingly-beleaguered Allardyce.
West Ham started their 5-0 defeat at Nottingham Forest with youngsters Daniel Potts and Callum Driver alongside midfielder Alou Diarra in a three-man defence.
Johnson’s stock has fallen following relegations in each of the last three seasons, firstly with Birmingham City and then twice with Wolves.
He was also involved in controversy at Wolves when he was punished by the club for turning up to training under the influence of alcohol.
However, prior to that he had been highly-rated, playing a key role in Birmingham’s impressive 2011 League Cup triumph, and forming a successful partnership with Scott Dann as the Blues finished 9th in the 2009/10 Premier League.
The move to West Ham could be seen as one last shot at the big time for the former Wycombe Wanderers and Cardiff City star.
Allardyce is expected to hand Johnson a baptism of fire by starting him against Manchester City at the Etihad Stadium on Wednesday night in the Capital One Cup semi-final first leg tie.
The West Ham boss has been given the backing of his club’s co-chairmen David Gold and David Sullivan, who posted an open letter on the club’s website today.
Gold and Sullivan voiced their support for Allardyce, who has never been relegated from the Premier League, and indicated that they expected Andy Carroll, Reid, Collins and Tomkins to return soon.
They added: “We understand these are difficult times for the Club and its supporters, but we must stay united and come through the other side together. Please support us and the team - we have no desire to be where we are and we are all doing everything in our power to improve this unenviable situation.”
image: © Ben Sutherland