New Charlton boss Pardew is prepared to sacrifice £3.7m (€5.6m) Diawara as well - taking Pompey’s out-of-favour Andy O’Brien in a straight swap – to refresh the Addicks’ battle against relegation with some new faces. He has already signed Manchester City’s Ben Thatcher.

Redknapp, who has also signed French Under-21 international midfielder Arnold Mvuemba on loan from Rennes for the rest of the season, has another opportunity to the best out of a player another club have given up on.

Traore, a 26-year-old Mali international, has played only 13 games for Charlton since former manager Iain Dowie paid £2.3m (€3.5m) for him to Liverpool in the summer.

His arrival at Portsmouth gives Redknapp experienced cover at left-back for the injured Dejan Stefanovic and Noe Pamarot – and means he can return Matt Taylor to the midfield for the clash the Blades.

Traore sustained a stress fracture of the left leg after only three appearances for Charlton, having been sent off on his debut against West Ham.

Redknapp said: “I am very happy to have Djimi. I’ve followed his career for a long time at Liverpool and wanted to sign him in the summer. I watched him help Liverpool knock Chelsea out of the Champions League in a goalless draw when he was man-of-the-match at Stamford Bridge. He is big and strong and versatile, with a great left foot, just what we will need at Sheffield United.”

Redknapp will be the fourth manager in little more than six months for Traore, who has signed a two-and-half year contract with Pompey and said: “It is a great opportunity for me to come from a side fighting relegation to one trying to win a European place.

“I’m really grateful to Harry Redknapp for giving me this chance and I know I have to repay his faith in me. I only came back into the Charlton team in November and I played more games for Les Reed than Iain Dowie who signed me.

“But this is a chance too good to miss because like most players I have ambitions and feel I can fulfil them here.”