barcelona temporarily opened up a seven-point lead over real madrid at the top of la liga .
argentina superstar lionel messi opened the scoring with a trademark curled finish after 33minutes .
second-placed real madrid play rayo vallecano later on wednesday evening to close the seven-point gap .
luis suarez doubled the catalan 's lead with a similarly curling left-footed stunner after the interval .
barca defender marc bartra netted the third with a far post header from xavi 's whipped in cross .
former liverpool striker suarez tapped in a late goal from pedro 's cross in injury time to complete the rout .