In a rearranged fixture, the Royals never got going against Martin O'Neill's men and a resounding beating left them prime candidates for relegation as they struggled to adapt to life in the top flight.
A major upturn in form has occurred since, however - they are unbeaten in five games - and they find themselves out of the bottom three as a result.
A penchant for comebacks has helped their cause, with come-from-behind wins against West Brom and Newcastle followed by Wednesday's rescue of a 2-2 draw against Chelsea, and McDermott believes that they will present Sunderland with a tougher test this time around.
"The lads are fired up for every game and this one is no different," he told a press conference. Sunderland played well against us at the Stadium of Light, got an early goal and went from there.
"But we know it won't be easy for them to come here now with how we are playing and long may that continue."
The Black Cats are currently sitting in mid-table after some struggles of their own, but primed themselves for a surge in the second half of the season with the £5million acquisition of Swansea striker Danny Graham.
"When they and Martin started the season it was difficult, but look at them now," McDermott said.
"They're comfortable in the league and once again Martin is doing a great job, which he always does. He's got good players in and signed Danny Graham and I'm sure he'll be involved."