Victory over West Ham on New Year's Day has given the club fresh impetus but Meulensteen is aware his team face another huge test on Saturday.
"West Ham was hugely important, which we came out from really, really well. We had a great result and a good performance," he said.
"Sunderland is likewise. It is a huge game for us, it is a huge game for them, but we are being positive, have been working well and working hard.
"The quality has been there and it is starting to pay off. Hopefully that will be the same against Sunderland.
"It is good for us that it is played at home because it gives you that slight advantage with your own fans, so hopefully that will help us get the win."
Fulham have also received a boost with the news that captain Brede Hangeland could make his first appearance since the 4-1 win at Crystal Palace in October.
The 32-year-old centre-back underwent surgery in December to clear sciatic nerve trouble and Meulensteen said: "Brede is coming with full training with us, so he is up for selection in that respect, so he has done really, really well and is progressing nicely.
"It is up for us to decide whether he is okay to start. We haven't made our mind up completely, but I am very happy that he is up there for selection.
"But when people come back from a long injury, the last thing you want is to come back and then go again. We want him to come and stay, so we will be very, very cautious."
Goalkeeper Maarten Stekelenburg could also return and will have an ankle complaint assessed before the match, while full-back Kieran Richardson is available after hamstring tightness to face his former club.
Bryan Ruiz may well be left out of the squad after Meulensteen confirmed the Costa Rica international can leave in January, with Real Betis and a return to Holland among his possible destinations.