Brook showed balls and spirit but let's be honest if that fight went on another two or three rounds it would have been a nasty beat down and potentially career changing. Brook done well in the 2nd and 3rd but he was out of his depth in the end. He would clean Khan out though
That eye injury doesn't happen, then the outcome of that fight is very debatable depending on Brook's stamina down the stretch.
Facts from that fight - Brook boxed his head off early, made GGG miss and took some good shots and was able to keep his head and keep throwing, and unexpectedly hurting GGG.
I think GGG would have stopped him late around the 10th because he was cutting corners intelligently, but he would have took a beating to get there. Sadly we'll never know; denied a true classic.