The 52-year-old was unhappy with the performance of match official Damir Skomina after Chelsea were denied a penalty claim in a 0-0 draw with Dynamo Kyiv on Tuesday night.
Talk about the positives instead of the referee. You get bored of it
Mourinho is currently facing a fresh FA charge after he accused Premier League referee Richard Madley of being afraid to award Chelsea a spot-kick in a 3-1 defeat by Southampton earlier this month.
Former Manchester United captain Keane, who had his run in with referees over his career, admits he has grown bored of Mourinho’s constant complaints over the performance of match officials.
“You get bored of Mourinho after a while when he keeps going on about the referee instead of looking at the positives,” Keane told ITV Sport.
“Chelsea are getting back to their best. I’m sure he spoke to his players and staff about getting back to basics. They should have won the game. They should have had a penalty. Talk about the positives instead of the referee. You get bored of it.”
Keane continued: “The players get fed up and bored of it. There are positives: they played really well, couple of clean sheets in a row, they’re starting to get back to their best and they should have won.
“Instead the manager again and there is a lot of negativity around the place.”
Chelsea are in third place in Champions League Group G after collecting four points from a possible nine from their opening three games of the campaign.
The defending Premier League champions make the trip across London to face West Ham United this weekend.
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