The Portuguese coach finally put pen to paper on a three-year deal with the Red Devils on Friday morning after days of speculation linking him to the job.
Mourinho joins an array of top managerial talent in the Premier League, which now includes the likes of Klopp, Pep Guardiola and Arsene Wenger.
However, former Arsenal defender Keown has suggested that he would rather play for Klopp at Liverpool than any of the other bosses.
Speaking to the Daily Mail, Keown said: “There has never been a better time to be a Premier League player — just look at that array of coaching talent.
“Jurgen Klopp excites me most.
“He looks like he is with his men for every step, every pass, every high and every low. I like his positive vibe and when I’m watching him, I’m thinking: ‘He’s up for the fight and I wish I was fighting alongside him’.”
Klopp was appointed as Liverpool’s new manager back in October after the Merseyside outfit opted to sack former boss Brendan Rodgers.
The German coach is now preparing for his first full Premier League season in charge at Anfield.
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