Barcelona's defense leads the league by a wide margin with just 6 goals allowed in 18 games this season of Spain's top division. In their eight league games played in front of their supporters this year, Betis only allowed 5 goals. This season, very few teams have been able to muster many shots on goal against them. Given that Real Betis has only lost one league game at home since the season's beginning, they ought to pose a formidable challenge to Blaugrana in this match. In this game, I believe goals will be scarce, so I'd go with the under 2.5 prediction.