Former Arsenal defender Martin Keown says Old Trafford has lost its fear factor.

The Gunners knocked Manchester United out of the FA Cup last night.

"When you have performances like this, as Arsenal you look back and see it as a defining moment," Keown told BBC 5 Live.

"I think the aura of Old Trafford has slipped away now.

"They've lost nine games here in the last two seasons and under Alex Ferguson, that was six seasons worth of defeats."