Barcelona might have proved their superiority in Spain with last week's sumptuous 3-0 win at Real Madrid, but the Primera Liga remains Europe's toughest and most open division. Spain's top eight are covered by just six points, with Barca only ahead on goal difference from upstarts Osasuna. In Europe's other big leagues (England, Italy, Germany and France), the leaders are at least five points clear, and at most there are three teams within six points of the top. Spain stands alone in producing highly competitive games across the league, allowing no room for error or relaxation from even the best sides. This is what makes it so attractive to watch, and so difficult to bet on. Barcelona should open a sizeable gap sooner rather than later, especially now they have qualified for the knockout stages of the Champions League and can concentrate on their domestic ambitions. Racing Santander are the latest lambs to the slaughter in the Nou Camp, where the fans have seen Barcelona score 18 goals in their past five matches (with only one against). Racing have been hard to beat on their travels and a draw wouldn't be a total shock, but they won't be full of hope after a run of eight straight defeats (by an aggregate of 20-4) at the Nou Camp. Real Madrid do not rate highly for their visit to Real Sociedad. The home side are 10th and Madrid haven't taken a single point in four matches against top-half teams. What's more, Madrid don't have a great record at Sociedad - five defeats in their past 10 visits. The best home bet is Osasuna, whose clash with Alaves looks to be one of Spain's rare one-sided affairs. Alaves have won away against two of the three teams below them in the table, but they will find it tough against Osasuna, who are six-for-six at home. The best chance of an upset lies with Cadiz. They will travel with plenty of hope to Betis, who have yet to win in La Liga following a European game. Best homes: Sociedad, Getafe, Osasuna. Best aways: Cadiz, Sevilla.