The towering French defender finally joined Pompey in midweek after a protracted pursuit and was handed a surprise start in midfield to plug the gap left by the sale of Pedro Mendes to Rangers.

Redknapp insisted he had few alternatives at his disposal, but remains confident Kaboul will become an important figure for the club after a difficult debut.

Redknapp said: 'I had to throw Kaboul in to play in midfield and obviously he found it difficult.

'I had to play the lad in midfield and he had not had a pre-season game. I brought Kaboul in to play centre-back, but I lost Pedro on Thursday – not that I wanted to but we needed to get some money back in.

'I also lost Sulley Muntari from last season who gave us fantastic energy.

'He could run, tackle, cover the ground and shoot. He's been a big loss.'

Redknapp did not rule out using the Frenchman in midfield again and believes his new signing will improve with match fitness.

Redknapp said: 'I didn't bring him in to play in midfield, but the lad needs to get fit.

'He hasn't had any pre-season games and you need those games to get fit. I threw him in at the deep end and it was difficult for him.'

But the Blues boss was less forgiving of his side's defensive display as the defensive bedrock that secured the FA Cup last season crumbled away alarmingly.

In fact, Redknapp was quick to vent his fury at his back four from the touchline after a series of mistakes

All four defenders looked rusty, while David James has certainly had better days in goal.

Redknapp said: 'Some of the defending was just basic errors.
'We hit a goal-kick, John Terry headed it forward and Joe Cole was suddenly through on our goal.

'As a nine-year-old kid, if you see that their defender is going to win the header, you drop off.

'It's so easy, it's almost scary.
'We ended up standing there just watching and then having to chase it. That's how we defended all day – it was poor.'

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