The Royals booked their place in the last 16 of the prestigious competition with a straightforward 4-0 win over npower League One side Sheffield United.
McDermott has taken the Berkshire club to the quarter-finals on two occasions since he took over, claiming some famous scalps like Everton and Liverpool on the way.
He has also become a master at getting the best out of his teams in the second half of the season, and appears to be working his new year magic again with the club now on a four-match winning streak.
That run has created a huge boost in confidence at Reading, and for that reason their manager sees no reason why his team cannot reach what would be only their second cup semi-final in history.
"There's a buzz around the place at the moment and that comes from winning games," McDermott said.
"If we can win another game we're in the quarter finals - and we've been there before and we'll try and go one further again.
"The only thing that mattered was going through (yesterday)."
- Sports & Recreation