Jean-Alain Boumsong wants to win the critics over for the good of the Newcastle United manager, as much as himself.

The £8m Frenchman has looked anything but value for money this season after a string of errors, most notably a horror show in the 2-0 defeat to Manchester United this month.

That display alone fuelled the belief that Boumsong is not capable of becoming a defensive lynchpin in the Premiership, but he feels that is not a fair assessment.

The centre-back, signed from Scottish champions Rangers in January, is a regular for the France national team and is eager to prove his worth at St James' Park.

He helped keep a clean sheet in Saturday's 1-0 win over Manchester City, Newcastle's second victory in six days.

Boumsong said: "I have been disappointed with my own form but it is getting better. Adjusting to the Premiership is never easy and in a few games, particularly against Manchester United, I held my hands up. I was to blame.

"But the only way I am looking at it is that I will learn from it and I will become a better player in the future. I play in the French side so I know I can play, but I am the first to admit I have not been at my best. I don't know why. All players go through this and I know it will make me stronger."

Boumsong is as relieved as anyone that his displays have dramatically improved in the past two weeks, coinciding with Titus Bramble's return to fitness.

Now the 26-year-old, who made his name with Auxerre before moving to Scotland and to Rangers, is eager to repay the man who decided to splash big money on him - Graeme Souness.

A dreadful start to the season has meant that Souness still remains under pressure, despite two successive victories.

Boumsong admits he felt the manager's plight personally when he knew his mistakes were helping to pile up the pressure on the Scot's shoulders.

"My main concern is for the fans and obviously for the manager," said Boumsong, looking for the recent revival to continue at Portsmouth on Saturday. He sends us out on to the pitch and can't do anything then. It's up to the players.

"When I make mistakes I think only of the supporters and the manager because I have let them down.

"But I am strong character.

"The manager knows he needs results - we all do - and we will be doing all we can do make the job easier.

"All we are interested in as players is doing our best for the boss and the fans. Nothing else matters. When you give a goal away you feel awful, it's the worst feeling in the world, because all you want to do is win.

"I have been annoyed with my form and I know I can play better but by the end of the season I will show my best side.

"The manager has been magnificent and he allows the players to express themselves.

"He's a winner and I believe he will get the club back into Europe. All the players feel the same way. He is a very strong character.

"He won't settle for second best and he will do a great job at Newcastle."

Newcastle are expecting to have Kieron Dyer back from injury at Fratton Park but Emre and Nolberto Solano are still ruled out with similar problems.

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