"The doctors said it is not serious and in two or three days I should be fit," he told Reuters after training separately from the rest of the squad at their central Pretoria base because of the knock he picked up on Friday.
"Today I had an MRI, hopefully the result will be good and I will train soon and play on Tuesday."
The 20-year-old, sporting red strapping on his left knee, can also sleep easy over his decision to sign a deal to move to Turkish club Fenerbahce before the World Cup rather than wait to see if he caught the eye of a more glamorous club.
"I wanted to be sure before the World Cup, because you never know what can happen. I didn't want to be worrying," he said about his decision on Thursday to move from Chelsea, where he made just five substitute appearances in four years.
"I decided with my agent that it would be better for me to know where I'm going to play next season. We wanted to do this before the World Cup so now I can concentrate just on the national team."
Stoch, who was swung around by his arms and legs by his mischievous coaches, will avoid being pulled this way and that by clubs ready to pounce on previously little known players who make their mark on the international stage.
The shortest member of the Slovakia squad, at 1.68 metres, Stoch is a key member of the team and enjoyed an excellent season on loan at Twente Enschede, helping them win the Dutch championship this year.
Slovakia are appearing in their first World Cup finals as an independent nation and have been drawn in Group F with world champions Italy and Paraguay as well as New Zealand.
