MANCHESTER -- Jose Mourinho has said Manchester United fans may not see the best of Alexis Sanchez until next season.

Sanchez has scored once in nine appearances since arriving from Arsenal in the January transfer window and he will be back in the spotlight on Tuesday night when United take on Sevilla for a place in the Champions League quarterfinals.

But Mourinho insists it may be a while until the 29-year-old hits top form at Old Trafford.

"He's always the first out on the training pitch," Mourinho told a news conference on Monday. "Criticism? Right now in England there's criticism for almost everyone -- not everybody but almost everyone.

"He's not a kid -- he's a lad with many years of football and many years of experience.

"I don't think a player from a club like Barcelona and a national team like Chile is easy. It brings pressure. I am sure next season will be even better than this, that's normal."

Club captain Michael Carrick has first-hand seen what Sanchez can do in Premier League clashes with Arsenal.

Carrick was in the United team when Sanchez scored twice in a 3-0 Arsenal win at the Emirates in October 2015 and the 36-year-old believes the former Barcelona man will come good at his new club.

"He just loves the game," Carrick said. "He absolutely loves the game and every day in training he is the first one out with the ball at his feet, which is great to see.

"He is desperate to do well. He gives everything, he has done it for so many years now, we know exactly what he brings and he will have a great time here.

"I said when he first signed, he is a Man United player, he suits the way we play, he has got that excitement, he always looks forward, he is dynamic and in the end you can judge him in the first few games or whatever but I think over time he will be terrific and I have no doubts about it."