Barcelona match against Leganes was tough with their attackers struggling to score. But luckily Leganes defense made mistake that led to own goal helping Barcelona win 3 points. Even though score was not perfect Barcelona increased their lead over Real Madrid making their chances of winning title stronger. And that is right they are doing great in Champions League and also have good shot at winning Copa del Rey which could make this season very successful for them. With their current performance Barcelona is in good position to win multiple titles.
The match between Barcelona and Leganes was indeed very fierce and you are right, if for example the Leganes defenders did not make mistakes, the result of this match would most likely be a draw. But because of the mistakes of the Leganes defenders, Barcelona managed to win this match and take home 3 full points. Besides, to be honest, I didn't think that Barcelona would have difficulty in this match. Considering that Leganes is not a team that is not too favored, so I thought that this match would be quite easy for Barcelona. But in reality Barcelona was made difficult in this match. In addition, Barcelona is currently 7 points ahead of Real Madrid, with this Barcelona does have a greater chance of getting a trophy this season. Especially if for example Real Madrid cannot get maximum results in the match tonight. 
Because tonight Real Madrid will face Alaves. If you look at the facts, Alaves is actually not a team that will make it difficult for Real Madrid. Because currently Alaves is stranded in 17th position in La Liga. So with this, it is likely that Real Madrid will also get 3 full points in this match. Because if you look at the head to head record, it is already clear that Real Madrid is far superior to Alaves. Because of the 5 meetings between Real Madrid and Alaves, Real Madrid managed to sweep all of those matches with a win. So most likely Real Madrid can definitely win this match. But if for example Real Madrid performs badly again like in the previous matches, I think the worst result that Real Madrid can get is a draw.
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