IMO,Liverpool wants Barry AND Striker and/or Winger.
so if Barry is 20mil deal,10 left.for Xabi let's say they'll have another 18/20.
So with 30 almost 20 mil,you can buy the Winger/or/and Striker needed.
Without Selling Xabi,they'll have to pass on Barry,wich i believe they dont wish to...
