The former Chelsea manager has reportedly agreed to take over the helm at Old Trafford.
Ibrox side Rangers lost to Hibernian in the final of the Scottish Cup on Saturday.
Tony Cascarino is backing Mart Hughes as a candidate for Everton.
Hibernian beat Rangers 3-2 on Saturday afternoon, and Everton offered congratulations and commiserations.
Spurs have been linked with the German international.
The 19-year-old will be joining Watford from the start of next season.
Spurs are believed to be considering the sale of Son.
Former Rangers ace Nigel Spackman predicts that Mark Warburton will stay at Ibrox for some time.
The former Chelsea manager has been heavily linked with Aston Villa in recent weeks.
The Everton youngsters made their debuts this season, and the Blues are apparently keen to tie them down.