Barcelona football team played very well in the last match which they played against Rayo Vallecano football team and that team won the match by doing 1 goal in this match. Lewandowski was the person who did one and only goal of this match and he did goal at 28 minutes of the match and he did goal at penalty. Rayo Vallecano team players could not do any goal in this match which was very low quality performance by that team . The possession percentage of Barcelona team was excellent which was 60 percent and that of Rayo Vallecano team was only 40 percent and passes of Barcelona team were also more in number in this match and Rayo Vallecano team passes were only 354 in this match.
On the contrary Barcelona game was not good at all, because with the game system since the first half, Barcelona should have been able to score goals without the help of penalty kicks. Unfortunately even though the results brought Barcelona to the top of the standings and won 3 points over Rayo the game was still not very satisfying. Expectations for Barcelona ideal squad should be more than this, they have an extraordinary combination of attacks in pressing opponents but against Rayo it was not very visible.
I agree with you that Barcelona could have done better against Rayo Vallecano but you also need to understand that game was a very crucial one of which any mistakes could have led to the game ending in a draw or Barcelona even losing and won't have been able to top the table. Moreover, Rayo Vallecano is not in a bad form either regardless that Barcelona was far stronger than them so we still need to accord Barcelona some regards because if they were not able to win Rayo they could have faced backlash because such opportunity may have not present itself again, now they are topping the table even with the slight point difference but it still gives them confidence and morale to work harder in order to retain the top of the table.