I wouldn't bother with Mascherano to be honest, we have Yaya who while maybe not being a better tackler or as good as putting pressure on opponents he's big, strong, good on the ball and links very, very well with Xavi and Iniesta when that trio are in midfield. When Yaya isn't playing we have Busquets who has proven to us that he deserves recognition for his talents and more chances next season.
If were gonna try sneaking any player from Liverpool why not have a go at Torres. Think they'd be interested in Eto'o and Hleb?