Germany thrashed Australia 4-0 in their opener while Serbia lost 1-0 to Ghana and need top pull off a shock result against the three-times world champions to boost their chances.
"They have a plethora of versatile players and are difficult to contain but we will be no pushovers," said winger Zoran Tosic, who could be brought in to spice up the attack.
"There is no more room for error and we have to show what we are made of," he said of the game at Nelson Mandela Stadium.
"Subotic is a natural replacement for Lukovic and I am confident he will do a good job in what is now a crunch game against the Germans," Antic said.
Zdravko Kuzmanovic, who conceded a late penalty against Ghana, is likely to replace the ineffective Nenad Milijas as Serbia aim for a first win over one of the world's top-ranked sides since the country's separation from Montenegro.
"Their defence is good with lots of experienced players. Their midfield is very skilled and they like to play down the wings," said Germany's assistant coach Hansi Flick.
"Our team is very young... but they are a young generation that is extremely confident, who know exactly what they want.
"Serbia will play (as if it's) their last chance to remain in the tournament. We have to be as careful as hawks when we play them," he added.
