Portsmouth manager Harry Redknapp admits his side could suffer an FA Cup capitulation if they do not improve their 'dreadful' defending.Pompey were defeated 3-1 by Everton in the Premier League on Sunday and Redknapp has lamented his side's defensive performance at Goodison Park.

He has been critical of midfielder Sulley Muntari and he believes all three of Everton's goals could have been prevented.

The Pompey boss is demanding his side, who had drawn level at 1-1 after falling behind to an early Aiyegbeni Yakubu strike, make drastic improvements when they travel to Old Trafford to take on Manchester United in the quarter-finals of the FA Cup on Saturday.

"The defending for the goals on Sunday was dreadful," Redknapp told the Portsmouth News. "With 20 minutes to go I couldn't see us losing. It was even stevens.

"Then Tim Cahill came with a free header because we didn't track him. It's no surprise he does that. We worked on it before the game.

"So for Sulley Muntari to track him halfway and then switch off was frustrating. We had a dreadful start, got back into the game and did that.

"We have to work on it because if we think that was tough just wait until Saturday. That's going to be even tougher. Everton are a strong team but United are on another level.'

"The defending was terrible for the first and third goals, too. Terrible."

Redknapp confesses he will be forcing his squad into a lot of hard work on the training ground as they bid to stop a United attack expected to be containing the likes of Wayne Rooney and Paul Scholes.

"It's something we'll be working on this week. It's something we have to look at closely, that's for sure," Redknapp added.

"Wayne Rooney likes to arrive late and so does Paul Scholes, but they are just world-class players. But United have them all over the pitch and on the bench."

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