Shawn Michaels was involved in a feud with the Undertaker towards the beginning of 1998, leading to a casket match between the two at the Royal Rumble.
It was in this match that Shawn Michaels suffered two herniated discs and a completely crushed disc in his back. He had a final match at WrestleMania where he handed the torch to Steve Austin and was thought to have retired.
However, he recovered enough to return to what he loved and began wrestling again in 2002.