Speaking after last night's 3-0 drubbing at home to Watford, Coppell attacked supporters who have been barracking beleaguered midfielder Andy Hughes.
"I must say that the cheering when Andy Hughes was brought off was terrible," said the Royals boss, speaking to Reading World.
Despite some poor recent performances, Coppell is fully behind his enthusiastic midfielder.
"He gives so much on a weekly basis and for some Reading fans to treat one of their own players in that way was totally out of order.
"He's bemused by the way he's been treated and the way he was cheered when he was brought off. I'm lost for words when some supporters do that to one of their own players."
Last night Hughes was twice given acres of space in which to charge at the Watford defence on the counter attack. But the 26-year-old failed to make anything of the opportunities, tamely shooting the first time around and giving the ball away on the second occasion.
However, it must be said that Coppell's replacement for the under-performing Hughes was a similarly below par James Harper.
Despite Coppell's harsh criticism of the Reading support, it remains to be seen whether he will name Hughes in his starting line-up for our league game at Watford this weekend.