Rosberg took his sixth pole position of the season at the Hungaroring on Saturday, while Mercedes team-mate Hamilton was eliminated in the early part of Q1 when his car caught fire.
While Hamilton charged through the field last weekend at Hockenheim to finish on the podium, the Hungarian circuit is traditionally one of the hardest to overtake on in F1.
"It makes it easier of course because he is my competitor," said Rosberg. "It's a free opportunity tomorrow.
"I need to play it safe and avoid any unnecessary things happening and get as many points as possible.
"Also I would prefer to be out there battling with Lewis, that would give me the maximum adrenaline rush.
"It won't be a gloves-off battle with Lewis but I am still very, very happy."
With both Mercedes drivers suffering reliability issues in recent races, Rosberg admitted that it remains a concern for the team.
"It's massively disappointing when the car breaks down," he said. "I had it two races ago at Silverstone.
"It's tough, not something you can control. It's a pity for the team, not a good thing and we need to keep working on it."
As much of Mercedes' advantage this season has been attributed to the manufacturer's engine, Rosberg said it was significant for the team to still be leading the way on a track that has so few straights.
"I have been surprised that we have been able to be so quick this weekend," he added.
"Our engine is definitely very, very strong and here the engine doesn't come into play so much, so it shows how good our car is.
"With FRIC not being on the car, we are still finding our way, so with lots of long corners here I am pleased with where we are."
- Sports & Recreation