Aleksandar Mitrovic has spoken about the injury which led to him being stretchered off at St Andrew's.
The Newcastle United striker was given oxygen as he was carried off the field in Saturday's 1-1 draw against Birmingham City.
Mitrovic had suffered a badly gashed leg in the build-up to Daryl Murphy's goal in the third-round FA Cup tie.
There were fears the Serbia international had suffered a break or ligament damage.
But the 22-year-old could be back playing in a matter of weeks.
"The cut is major, but I feel good," Mitrovic told Blicsport. “Thank God it looks like the ligaments and knee are fine.
"However, I expect additional examinations. We have to be sure that there is no damage to the knee.
“The first forecasts are that I will not be on the pitch for three or four weeks. The cut is just in an inconvenient spot.”
Blicsport have published a graphic image of the cut, which was inflicted by the studs of goalkeeper Adam Legzdins as he attempted to block Murphy's fifth-minute shot.
Lukas Jutkiewicz netted an equaliser for Birmingham before the break to set up a replay on January 18.