According to the Daily Mirror's Andrew Gilpin, Besiktas coach Senol Gunes required stitches after he was hit in the head by an object thrown by the fans. The incident occurred in the 58th minute, and the match was eventually abandoned.
Assistant coach Erdinc Gultekin was also injured. Per the report, there was a tunnel bust-up, but most of the troubles took place on the pitch.
As you can see in the image below, Gunes was hit right on the top of his head:
Thursday's match was a cup semi-final between bitter rivals, and following an early red card for Pepe, things only grew more heated.
The two teams played out a 2-2 draw in the first leg of the semi-finals,. The Turkish FA will decide on a date to replay the second leg, which will likely take place behind closed doors. The winners will face Akhisarspor, who shocked Galatasaray 2-0 on Wednesday to become the first team to qualify for the final.