Arsène Wenger has praised Alexis's attitude and commitment, while dismissing claims that he returned from international duty overweight.
The Chilean was introduced during the second half of our 3-0 win over Bournemouth on Saturday, and the manager said he is looking in good shape after returning from a disappointing international break with Chile.
"He is disciplined, serious and committed," Wenger said after the game. "He is focused. He told me he is focused on the Premier League and Europa League. On top of that Chile had a bad experience, but he came back full of desire and was ready to play.
"He is not fat. His fat percentage is under ten, so that’s not fat, but you know how it is when you don’t win, people find every problem for you.
"He was not completely physically ready to start three games in a week and certainly for Chile he was not completely ready as well."
The boss added it was too early to say whether Alexis would be involved on Thursday evening against Cologne in the Europa League, but confirmed he would be taking the competition seriously.
"It’s a new experience for us," Wenger said. "We will take it seriously, but as I said, the priority is to focus on the Premier League and as well to manage to combine the two until December and at least qualify."
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