The Royals are pointless since securing their first Premier League win of the season against Everton in mid-November, although they have put up some decent performances in defeat since, most notably against Manchester United.
But McDermott conceded they were not up to scratch in the 1-0 defeat by Southampton at the weekend and he hopes they can put the record straight in their rearranged midweek clash at the Stadium of Light.
"You look at the four defeats and we definitely should have got something from the games that we've played," McDermott said.
"The Manchester United game last week we played really, really well but weren't solid enough. I thought our shape was much, much better against Southampton, but with the ball we weren't as good as we needed to be.
"We need to combine it all. Everything needs to come together. We're looking at the next game. That's the only thing that matters.
"What happened at Southampton has gone. There is nothing we can do about that. We're disappointed about that. It is very unusual from us that we went one goal behind and didn't respond the way we normally would do.
"The last three years I have always had great responses from the players and I didn't get that against Southampton so that was disappointing. I think the first goal was really important, for obvious reasons. We hit the post in the first half and if we could have got that then the game is different."
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