It was a bad day for the Black Cats, who were outplayed and beaten by a side ranked 54 places below them in English football.
And the 2-1 home defeat to Paul Ince's side was hardly ideal preparation for Sunday's derby, especially with the Wearsiders keen to put right the 5-1 thumping they received at St James' Park earlier in the season.
Malbranque admits the Black Cats were well below par against the League One side, but insists the players are eager to put both the FA Cup exit and the 5-1 defeat to Newcastle firmly behind them.
It was a massive disappointment because we wanted to have a really good run in the cup, said the Belgianborn player.
To lose to a lower-league team at home, where we have been so strong, is very bad for us.
The important thing now is we have to move on and get this out of our system quickly.
We have a massive game against Newcastle next weekend and that is one we are desperate to win.
We have to try and get on with things and we have to concentrate on the Newcastle game and hopefully we can put things right in front of our supporters in that one.
Not since the 2004-5 season, when they reached the semifinals of the competition, have Sunderland progressed beyond the fourth round of the FA Cup.
This season though, with the Black Cats currently sixth in the Premier League table, there was a sense of optimism on Wearside that Steve Bruce's men could go on a good cup run.
That feeling was also echoed by the players, but a disappointing performance has seen them knocked out of the competition at the first hurdle.
Malbranque admitted the players were hurting after the defeat, but insisted everyone must put their disappointment behind them and not let the result derail what has been a good season so far.
I have been in English football long enough to know what the FA Cup is all about,
Shocks do happen, this is exactly what this competition is all about. We knew it could happen and we should not have let it happen.
We didn't play well in the first half and they scored the first goal. That was ideal for them, they were able to drop back in numbers and they defended well. It wasn't a good day for us though, we had chances, but we didn't play well.
The cup competitions should have been something we did well in this season.
Our league position shows we are a good team. We must not let this bad result ruin our season because we are in a good position still.
If we can do something really good in the league, people will forget about the cup competitions. That is what we must focus on.