The Red Devils named the Portuguese coach as their new manager on Friday morning after months of speculation linking Mourinho with Louis van Gaal’s position.
The Dutchman was sacked just days after he led United to their first piece of silverware in three years following a 2-1 extra-time victory over Crystal Palace in the FA Cup final.
Southampton manager Koeman, who has been previously linked with Arsenal and Chelsea, insists United didn’t deserve to win the FA Cup if the Reds Devils had lined up Van Gaal’s sacking and Mourinho’s appointment ahead of the Wembley showpiece.
“I have watched the process around Louis and Jose Mourinho from a distance,” Koeman told Daily Mirror.
“For months we were all reading that Mourinho was busy with Manchester United. If Louis was not told about getting the sack until after the FA Cup final, then Manchester United as a club don’t deserve a medal for the way they treated him.”
Mourinho was sacked by 2015 champions Chelsea in December following a dreadful start to the defence of their Premier League campaign.
The former Inter Milan and Real Madrid boss becomes the third United manager since Sir Alex Ferguson’s retirement in 2013.
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