After giving away a penalty on Lamine Yamal during their hammering by Barcelona, Mojica turned on Morlanes, first headbutting him, then punching his teammate in the arm.
Morlanes reacted with surprise, though the pair carried on.
Afterwards, Arrasate said: "When we analyse the match, apart from the tactical aspect, we will also look at the rest. I am not justifying Mojica, but he is over-confident and that is what I have reproached him for, but we have all made mistakes. When we lose, we all do it."
He also said: “He's playing a lot, he's travelling with the national team and it's not easy. He made a few mistakes, especially in the play that led to the first goal. He was having a great season, but football is like that.
"A mistake against this type of team eats you up, we've made more than one and we've paid for it.”
Mallorca were hammered 5-1 on the night.
