The Croatia forward, who opened the scoring in rout of Cameroon, says he is a doubt to face Mexico after requiring stitches to a freak injury suffered in the team hotel
The experienced attacker opened the scoring against the African side on Wednesday, converting Ivan Perisic's pass from close range before Croatia romped to a 4-0 win.
The 34-year-old has since explained he forced himself to play through the pain after requiring stitches when a piece of glass became stuck in his right foot in the hours before the game.
"All the best to our medical team who enabled me to play after an accident I had in the hotel," Olic said after Wednesday's game, which saw him become the oldest Croatia goalscorer in World Cup finals history.
"After a shower, the door in my bathroom broke and cut me. And I stepped on one piece of glass that got stuck in my foot!
"Doctors, headed by Zoran Bahtijarevic, sewed my wound and gave me a pain-killing injection so I could play.
Luckily, it was my right foot. I was so mad and even aggressive when they told me they have to sew it, but now I am grateful to them."
Olic said he would be perfectly happy to take further injections in order to play in the crucial Group A clash with Mexico, should the injury fail to recover sufficiently after a few days of rest.
"I am not allowed to train, to sweat. Hopefully, it will heal in the next two or three days so I don't have to take pain-killers for the Mexico game, but of course I will take them if necessary," he added.