The 27-year-old came on as a second half substitute in his side’s 4-1 victory over Swansea City at the Liberty Stadium on Saturday, providing assists for Robin van Persie and Danny Welbeck.
The England international has been linked with a move to Chelsea in the summer transfer window after the Blues submitted two unsuccessful bids for the Red Devils forward.
But Schmeichel, who won four Premier League titles at United, reckons the Red Devils would find it impossible to replace Rooney if the former Everton youth graduate quit Old Trafford.
“They’re trying to buy the best players in the world. They don’t sell the best players in the world,” Schmeichel told Sky Sports.
“I cannot see why someone like Wayne Rooney should leave Manchester United and possibly go and strengthen a team like Chelsea or even Arsenal.
“Why would you do that? Why would you give away your best player? No-one can replace Wayne Rooney. There’s no-one else out there who can play the way that he plays.
“We’ve been searching for a midfielder this summer but it’s not an easy thing. It’s so difficult to come in and actually prove what’s already there.”
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