The Malian took his first goal with aplomb but it was his match-winning header that McDermott felt epitomised his effort.
"Jimmy Kebe is becoming phenomenal in the air," he said. "I was so pleased for him because he such a brave player both physically and mentally.
"He wants to get on the ball and I think the first goal was fabulous. He wins headers and is good in the air, that was a great finish today. Ian Harte has put it in there and Jimmy has had to finish it off and he was brave.
"It was late in the game as well so it is difficult to come back at that stage."