Complex sentence: At WrestleMania XX in 2004, White returned to referee the match between Chris Jericho and Christian; unfortunately, he re-injured his shoulder during the final three count of the match, forcing him to end his referee career.
Split into simpler sentences: At WrestleMania XX in 2004, White returned to referee the match between Chris Jericho and Christian. He re-injured his shoulder during the final three count of the match, thus ending his referee career.