Mori, who joins on a five-year deal from the Argentinian side, will wear the No 25 shirt at Goodison Park and admitted that as soon as he heard Everton manager Roberto Martinez was interested in signing him, the move was never in doubt on his part.
"I'm the type of player who likes to work hard in every training session and in every game," Mori told Evertonfc.com. "I train the way I play and I'm going to give it 100 per cent every time I go out there to play for Everton.
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"When I heard about Everton's interest, I didn't think twice. My agent told me about this opportunity and Everton did everything to bring me over and I wanted to come.
"I know it's a Club with a lot of history and a lot of good players have come from Everton, so I'm very happy to be here.
"I've signed for five years, so hopefully I can keep growing as a player and I can stay here for a long time."
Martinez stressed last week that signing Mori was not a move to replace young England defender John Stones, and having fended off interest from Chelsea in the 21-year-old Stones and Mori will compete for selection alongside regular Phil Jagielka.
Mori was in attendance for Everton’s 2-0 defeat to Manchester City last month, and he is already looking forward to performing in front of the Merseyside fans that gave him such a warm reception.
"I feel happy because the people here have shown me a lot of love and I'm very happy and comfortable here already," he added. "I saw the people at Goodison Park and I saw they were a family and all cheering the players and obviously I liked that atmosphere.
"The manager has told me that my teammates are very respectful, that it's a family club and I really love that as well. I've met some of my teammates already and they have helped me.
"I went to the dressing room and they were very polite people, people who like to work hard. I could see that and hopefully I can fit straight into the group, we can get along and do big things here."
Read more:
Stones can be England captain, says Martinez
Everton fans start funny new Stones chant to taunt Chelsea
Match report: Tottenham 0 Everton 0
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