Avila scored a third goal for his new club, but three goals conceded in six minutes saw Los Che win 4-2 on Sunday.
He later said, "It's complicated. It's not that I want to wash my hands of it. You catch me stunned because just when we are about to go in with Lo Celso, two goals come in a row, it catches us off-balance , we try to get the ball with him and push forward, but when a rival like this scores a goal against you, it becomes difficult to score against them again."
The Europa Conference League returns on Thursday for Betis with their visit to Mladá Boleslav.
Avila continued, "We have to turn the page, but before doing so we have to read it again and correct it , see what is right and wrong. The manager will tell us, but we are adults enough to realise what we did wrong, what we have to correct.
"More than eleven, the 30 or whoever, we are all equal. Don't say 'it was the manager's (Manuel Pellegrini) fault', no, it was everyone's. Betis is a family, we are all one and the manager will correct us and we will work for it."
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