The 40-year-old former Manchester United star took the brunt of a full-speed header from ex-Cardiff City and Inter Milan man Gary Medel, which left both players in agony.
Both players had gone for the ball as the game entered the final ten minutes, and Medel - despite being considerably shorter than Ibrahimovic - jumped up and smashed into the left side of the legendary Swede's face.
The pair both then crashed to the ground in a heap, clutching their heads in pain, with the AC Milan star's face pouring with blood from the impact.
Both were immediately seen to by doctors, treated and bandaged up.
It wasn't long before the injured Ibrahimovic rose to his feet to demand the referee to dish out punishment to Medel for his challenge, though, with the hope that the former Bluebirds man would at least see yellow.
However, much to the dismay of Milan's No. 11, Livio Marinelli decided not to give the Chilean - who came off worse from the clash - any punishment.
Medel was unable to continue following the clash and was quickly subbed off, whilst Ibrahimovic - in true Zlatan style - carried on playing.
AC Milan's draw with 12th-placed Bologna means the Serie A leaders missed out on gaining significant ground on second-placed Napoli, who still sit just one point behind them.